Oman

A drone attack that caused a fire close to the Barakah Nuclear Energy Plant in the United Arab Emirates has raised further concerns about nuclear security and military escalation in the Gulf as discussions of peace between Iran and the United States hang in the balance.

Barakah was the first nuclear power station to be built on the Arabian Peninsula. Here is what we know about it:

What is the Barakah Nuclear Energy Plant?

Barakah is a nuclear energy plant located in Al Dhafra, the largest municipal region of the emirate of Abu Dhabi. It is the UAE’s only nuclear power plant.

Construction of the plant began in 2012, and its first reactor became commercially operational in 2021.

The plant is located close to the border with Saudi Arabia, about 225km (140 miles) west of the UAE’s capital city, Abu Dhabi.

The facility features four pressurised water reactors, the most common type of nuclear power reactor. The model used here is the advanced power reactor 1400, a pressurised water reactor design developed in South Korea. Each reactor of this type has the capacity to produce 1,400 megawatts (MW), which is enough to power roughly 1 million homes.

According to the Emirates Nuclear Energy Corporation (ENEC), the plant’s reactors produce 40 terawatt-hours (TWh) each year, which is equivalent to about 25 percent of the UAE’s electricity needs. The website for the London-based World Nuclear Association also confirmed that Barakah, when fully operational, meets 25 percent of the UAE’s electricity needs.

According to a September report by the Abu Dhabi media office, Barakah had produced 40TWh of clean energy over “the past 12 months”.

Since nuclear power plants produce a lower amount of carbon dioxide emissions than conventional power plants, the ENEC said Barakah saves up to 22.4 million tonnes of carbon emissions each year, equivalent to removing 4.8 million cars from the roads.

What happened in the attack on Sunday, and how has the UAE responded?

Authorities in Abu Dhabi said a single drone strike caused a blaze to break out at an electrical generator outside the Barakah plant’s inner perimeter in the Al Dhafra region on Sunday. No injuries were reported, and officials said radiation levels remained normal.

The UAE’s nuclear regulator said operations at the Barakah facility had not been affected. “All units are operating as normal,” it said in a social media post.

In a statement, the UAE’s Ministry of Defence said two more drones had been “successfully” intercepted and the drones had been launched from the “western border”. It did not give more details.

The UAE’s Ministry of Foreign Affairs posted a statement on X on Sunday saying the country condemned “the unprovoked terrorist attack” in “the strongest terms”.

The statement added: “The UAE emphasised that it will not tolerate any threat to its security and sovereignty under any circumstances, and that it reserves its full, sovereign, legitimate, diplomatic, and military rights to respond to any threats, allegations, or hostilities in a manner that ensures the protection of its sovereignty, national security, territorial integrity, and the safety of its citizens, residents, and visitors, in accordance with international law.”

There was no immediate claim of responsibility, and the statements by the ministries did not publicly blame any country.

But Anwar Gargash, an adviser to the UAE’s president, wrote in an X post on Sunday: “The terrorist targeting of the Barakah clean nuclear power plant, whether carried out by the principal perpetrator or through one of its agents, represents a dangerous escalation and a dark scene that violates all international laws and norms, in criminal disregard for the lives of civilians in the UAE and its surroundings.”

Gargash’s post appeared to blame Iran and its proxy network of allied armed groups in the region, which Tehran calls the “axis of resistance”.

The launch point of the drones remained unclear, but on Sunday, Saudi Arabia also reported it had intercepted three drones that had been launched from Iraq, where some Iran-allied groups operate. If Iranian Shahed-136 drones, which have an estimated range of 2,000km to 2,500km (1,240 to 1,550 miles), were fired from Iraqi territory, both Saudi Arabia and the UAE would fall well within their reach.

Other reactions

Neighbouring Gulf states Saudi Arabia and Qatar condemned the attack on the Barakah plant.

The Ministry of Foreign Affairs of Kuwait also issued a statement denouncing the attack, which it called “heinous”.

The Indian Ministry of External Affairs condemned the attack, calling it “unacceptable”, saying it represented “a dangerous escalation” and urging a return to diplomacy.

Has Iran responded to the incident?

Iran has not claimed responsibility for the drone attacks, and there has been no public statement from Iran about the incident at Barakah.

However, in the aftermath of the drone attacks, United States President Donald Trump wrote in a Truth Social post: “For Iran, the Clock is Ticking, and they better get moving, FAST, or there won’t be anything left of them. TIME IS OF THE ESSENCE!”

Iranian Ministry of Defence spokesperson Reza Talaei-Nik said on Sunday that the military is “fully prepared” to confront any new aggression from the US and Israel.

Iran has previously warned that countries where US military assets are deployed or Israeli-linked interests are located are viewed as legitimate targets.

Iran has also accused the UAE of strengthening ties with Israel while reports have emerged that Israeli Prime Minister Benjamin Netanyahu made a “secret” visit to the Gulf state during the US-Israel war on Iran. The UAE has denied this.

US Ambassador to Israel Mike Huckabee also said last week that Israel had deployed Iron Dome air defence systems and personnel to the UAE to help defend against possible Iranian attacks.

What has the IAEA said?

The International Atomic Energy Agency (IAEA), the global nuclear watchdog, said Sunday’s incident in the UAE had forced one reactor to rely temporarily on emergency diesel generators.

IAEA chief Rafael Grossi expressed “grave concern” and warned that military activity threatening nuclear facilities was “unacceptable”.

How serious could a strike on a nuclear facility be?

Attacks on nuclear power plants are especially worrying because they can risk damaging critical safety systems or reactors, which could release radioactive material into the atmosphere, not only over the country targeted but also across neighbouring states. Radiological material, specifically the hazardous isotope Caesium-137, could be released into the atmosphere.

The release of radioactive material could result in environmental contamination and poses major risks to public health. Water, if contaminated, becomes undrinkable while farmland and fisheries could become unsafe for decades, depending on the isotope released.

Short-term, acute exposure to radioactivity can cause burns and acute radiation sickness, which can be life-threatening.

Prolonged exposure, even to smaller doses, can increase the risk of illnesses such as cancer, especially thyroid cancer and leukaemia. Children and pregnant women are especially vulnerable.

Over the course of the US-Israel war on Iran, energy infrastructure has become a target.

Iran’s only functioning nuclear plant, the Bushehr power plant, has come under repeated attacks in the war. There are fears that damage at Bushehr could contaminate water across the entire Gulf region, most of which lacks groundwater and relies heavily on the desalination of seawater. Desalination plants are not specifically built to filter radioactive material, and not all plants currently are fitted with the technologies required to do so.

Iran said on Wednesday that it was reviewing a United States peace proposal that sources said would formally end the war, while leaving unresolved the key US demands that Iran suspend its nuclear programme and reopen the Strait of Hormuz.

An Iranian Foreign Ministry spokesperson quoted by Iran’s ISNA news agency said on Wednesday that Tehran would convey its response. US President Donald Trump said he believed Iran wanted an agreement.

“They want to make a deal. We’ve had very good talks over the last 24 hours, and it’s very possible that we’ll make a deal,” Trump told reporters in the Oval Office on Wednesday.

A day before, Trump paused “Project Freedom” to reopen the blockaded strait, citing progress in peace talks. The de facto blockade of the waterway threatens to cause a global recession. Iran has been pressing to keep Hormuz under its control, through which a fifth of global oil and gas supply passes.

Here is more about the US proposal to end the war, and how experts think Iran would respond.

What is the latest US proposal to end the Iran war?

US media outlet Axios said the two sides were “getting close” to an agreement on a 14-point document. Under the memorandum, Iran would agree not to develop a nuclear weapon and halt enrichment of uranium for at least 12 years, it said.

The US would lift sanctions and release billions of dollars in frozen Iranian assets, and both sides, which have imposed competing blockades in the Strait of Hormuz, would reopen the critical waterway within 30 days of signing.

Iran has been under US sanctions for decades, and the lifting of some sanctions under the 2015 nuclear agreement was reversed after Trump walked out of the landmark deal signed under his predecessor, President Barack Obama. Billions of dollars of Iranian assets remain frozen in foreign banks due to the sanctions.

It is unclear how this memorandum differs from a 14-point plan proposed by Iran last week.

The Reuters news agency reported on Thursday, citing a source briefed on the mediation, that the US negotiations were being led by Trump’s envoy Steve Witkoff and son-in-law Jared Kushner. If both sides agreed on the preliminary deal, that would start the clock on 30 days of detailed negotiations to reach a full agreement.

The full agreement would end the competing US and Iranian blockades on the strait, lift US sanctions and release frozen Iranian funds. It would also include certain curbs on Iran’s nuclear programme, which was allowed by the United Nations nuclear watchdog.

While the sources said the memorandum would not initially require concessions from either side, they did not mention several key demands Washington has made in the past, which Iran has rejected, such as curbs on Iran’s missile programme and an end to its support for armed proxy groups in the Middle East.

The sources also made no mention of Iran’s existing stockpile of more than 400kg (900lb) of near-weapons-grade uranium.

Israeli Prime Minister Benjamin Netanyahu, Trump’s ally, said on Wednesday the two leaders agreed that all enriched uranium must be removed from Iran to prevent it from developing a nuclear bomb.

The US and Israel bombed Iranian nuclear sites last June during the 12-day war, after which Trump claimed that Tehran’s nuclear programme was obliterated. A significant portion of Iran’s enriched uranium stockpile remains buried inside the bombed nuclear sites.

Tehran denies wanting to acquire a nuclear weapon. It insists its programme is for civilian purposes as allowed within its position as a signatory to the non-proliferation treaty.

Could Iran agree to this proposal?

Iran has yet to formally respond to the latest US proposal. However, Iranian leaders have pushed back against it.

Iranian lawmaker Ebrahim Rezaee, a spokesperson for the parliament’s powerful foreign policy and national security committee, described the text as “more of an American wish-list than a reality”.

Iran’s Parliament Speaker Mohammad Bagher Ghalibaf appeared to mock reports that the two sides were close, writing on social media in English that “Operation Trust Me Bro failed.”

Al Jazeera’s Resul Serdar Atas, reporting from Tehran, said on Thursday that Iran is still reviewing the US proposal, after which a response is expected to be given to the Pakistani mediators later today.

The Pakistani Ministry of Foreign Affairs said on Thursday that it welcomes the news of a potential agreement between Iran and the US, adding that it will not disclose additional information at this stage.

“As mediators, we will not lose the trust of both parties by revealing details,” it said in a statement quoted by Al Jazeera Arabic.

Atas said, “Iranians are saying that, at this stage, they’re not negotiating their nuclear programme; it’s only about ending the war on all fronts.”

He added that Tehran wants direct guarantees from the UN Security Council, a lifting of sanctions and the reopening of the Strait of Hormuz.

“If that is achieved, in a second phase, they’re ready to discuss their nuclear programme.”

Al Jazeera’s Almigdad Alruhaid reported from Tehran on Tuesday that Iran has set “a very firm red line” on the nuclear file. “The nuclear enrichment programme is non-negotiable,” he said.

According to former US Assistant Secretary of State Mark Kimmitt, Trump’s reported demand that Iran halt all uranium enrichment is unrealistic and unlikely to be accepted by Tehran.

“If there is anything the Iranians are going to insist upon in these negotiations, it is their right to enrich uranium to the 3.67 percent level, which is allowed under nuclear non-proliferation treaties,” he told Al Jazeera.

Kimmitt added that even the 2015 nuclear deal permitted Iran to continue enrichment. Iran boosted its enrichment up to 60 percent after Trump withdrew from the deal in 2018, during his first term.

However, Kimmitt postulated that Trump might want Iran’s existing stockpile of enriched uranium outside of Iran. He added that Iran might either agree to move the enriched uranium outside the country or dilute it down to a non-enriched state.

Alruhaid, the Al Jazeera correspondent, however, said Iran is resisting handing over its existing stockpile of enriched uranium.

Iran is believed to have about 440kg (970lb) of uranium enriched to 60 percent. A 90 percent threshold of enriched uranium is needed to produce a nuclear weapon.

Al Jazeera’s Alruhaid said “the sovereignty on the Strait of Hormuz is becoming one of the main issues on the negotiating table.

“We are seeing the Iranians are tightening their control. They are setting new protocol, new mechanism for controlling that strategic chokepoint for each vessel that is to pass through.”

The US allies in the Gulf, who faced the brunt of Iranian retaliatory strikes, have been pushing for the restoration of navigation in the strait without any conditions. Iran carried out attacks on the Gulf nations, mainly targeting US military assets, after the US and Israel launched attacks on it on February 28.

Trump has repeatedly played up the prospect of an agreement that would end the war, so far without success. The two sides remain at odds over a variety of difficult issues, such as Iran’s nuclear ambitions and its control of the Strait of Hormuz.

A Pakistani source and another source briefed on the mediation told Reuters that an agreement was close on a one-page memorandum that would formally end the conflict, the agency reported on Thursday.

This agreement would kick off discussions to unblock shipping through the strait, lift US sanctions on Iran and set curbs on Iran’s nuclear programme, the sources said.

Al Jazeera, however, could not confirm the veracity of the reports.

United States Secretary of State Marco Rubio told reporters on Tuesday that Operation Epic Fury – the US-Israeli strikes on Iran which commenced on February 28 and prompted a regional conflict – had concluded as its objectives had been achieved. Washington now prefers “the path of peace”, Rubio said.

On the same day, US President Donald Trump announced that the US military operation to escort stranded ships out of the Strait of Hormuz – “Project Freedom”, which was launched the day before – had been paused.

So, does this mean the US-Israel war on Iran is over?

What did Rubio say about Operation Epic Fury?

In a media briefing at the White House on Tuesday, Rubio told reporters that Operation Epic Fury was over.

“The Operation Epic Fury is concluded. We achieved the objectives of that operation,” Rubio said.

“We’re not cheering for an additional situation to occur. We would prefer the path of peace. What the president would prefer is a deal,” he said, referring to Pakistan’s efforts to arrange direct talks between Iran and the US.

The first round of these, in Islamabad last month, ended without a resolution. Both sides have submitted new proposals since then.

“The on-again, off-again talks with Iran, alongside Trump’s abrupt about turn on ‘Operation Freedom’ to guide vessels out of the Strait of Hormuz has created unwelcome frenzy in the Gulf,” Burcu Ozcelik, a senior research fellow for Middle East security at UK-based think tank Royal United Services Institute (RUSI), told Al Jazeera.

“It also reflects the highly fraught and almost frantic diplomatic backchannelling aimed to extract deep concessions from Tehran on the nuclear issue that will lock in commitments that exceed previous conditions, and which will convince the US to lift the blockade on Iranian ports and unlock sanctions relief – thereby effectively ending the war.”

Ozcelik explained that Iran, on the other hand, wants guarantees that this will be the end of the war, rather than just a pause.

What did Trump say about Project Freedom?

The same day, Trump told reporters that Project Freedom had been paused “based on the request” of Pakistan and other countries, and the “fact that Great Progress has been made towards a Complete and Final Agreement” with representatives of Iran.

Project Freedom was the US forces’ operation to escort stranded ships through the Strait of Hormuz that Trump announced the day before. It had appeared to signal a direct challenge to Iran’s closure of the strategic waterway, through which 20 percent of the world’s oil and liquefied natural gas (LNG) supplies are shipped in peacetime. Iran’s threats to attack ships in the strait have blockaded it since the US-Israel attacks on Iran began. Then, the US announcement of a naval blockade on Iranian ports added to the standoff around the strait.

After Trump announced Project Freedom, Iran said ships trying to use the strait without permission from the Islamic Revolutionary Guard Corps (IRGC) would be fired on, igniting fears of a return to war. His announcement triggered a war of words between the US and Iran, with claims and counterclaims about strikes continuing throughout the day.

First, Iran’s Fars agency claimed it had hit a US warship with drones after it ignored orders to turn back from the Strait of Hormuz. US Central Command (CENTCOM) denied a US ship had been struck, however, and instead claimed to have sunk at least six IRGC vessels. Iran denied that. Tehran then published a new map extending its claimed area of control over the strait into UAE waters, raising fears of a new regional confrontation.

The UAE accused Iran of launching strikes on its Fujairah port, the site of an important oil pipeline, which sparked a fire in an oil refinery.

On Tuesday, the US operation had been stopped, according to Trump.

“We have mutually agreed that, while the [US] Blockade will remain in full force and effect, Project Freedom (The Movement of Ships through the Strait of Hormuz) will be paused for a short period of time to see whether or not the Agreement can be finalized and signed,” he wrote on his Truth Social platform.

Iran has not immediately responded to this.

Shahram Akbarzadeh, a professor in Middle East and Central Asian politics at Australia’s Deakin University, told Al Jazeera that while it is difficult to determine exactly why Trump has paused Project Freedom, the pause comes against the backdrop of growing antiwar public opinion in the US.

“At the same time, Trump may be losing patience with the war; he says he has time to drag this out,” Akbarzadeh said.

“But in reality, Trump has a short attention span and needs to secure a win – soon. Pausing Project Freedom allows diplomacy to pick up pace, bringing US and Iran closer to a deal that Trump would label as a win.”

Is this the end of the war on Iran?

Not exactly. Akbarzadeh said pausing Project Freedom could serve as “the beginning of the end for the war”.

“We know that the Iranians are desperate for an end, so there is little chance of them resuming attacks on US Navy if Trump sends explicit signals that diplomacy has a green light,” he said.

However, he added, “The problem is that we have been here before. Earlier opportunities were squandered because Israel insisted that the US could get a better deal or because Trump misread the situation and expected the military option to grant him more concessions.”

What happens next?

It is difficult to predict this, but neither side appears to want a return to full-scale war, so both are likely to prioritise a diplomatic way out, Akbarzadeh said.

Still, “neither can afford to be seen as the loser,” he added. “They feel their public image needs to be preserved for their own respective domestic audience. This complicates negotiations and reaching a deal.”

Ozcelik said what happens next “will be determined by what the fractured leadership in Tehran commits to on the nuclear file.

“While it has rejected that talks involve curbs on Iran’s nuclear programme, this type of posturing has aimed to assuage domestic, hard-line and Iranian nationalists who are rattled by the US-Israel strikes and see nuclear issues from a nationalist, sovereign rights perspective.”

She predicted that the United Nations may soon issue a formal condemnation of Iran for unilaterally blockading the Strait of Hormuz.

“But the real pressure, mounting by the day, is the economic one – that shutting the strait is imposing punishing costs on Iran’s economic recovery prospects,” she said.

“Despite rhetoric on resilience and survival, the remaining Iranian leadership is undeniably concerned about the costs of the war. The possibility of renewed military strikes against Iranian critical infrastructure and the destabilising impacts these would inevitably have might be finally forcing Tehran’s hand,” Ozcelik concluded.

Iranian commander says US military attacked two passenger boats, not IRGC vessels, in the Strait of Hormuz on Monday.

Iran has accused the United States of killing five civilians in the Strait of Hormuz, saying its forces attacked passenger vessels in the waterway rather than boats belonging to the Islamic Revolutionary Guard Corps (IRGC) as claimed.

The claim on Tuesday contradicted a statement by US Admiral Brad Cooper, who said Central Command forces had sunk six IRGC vessels that had attempted to interfere with a US mission to escort stranded ships out of the Strait of Hormuz.

US President Donald Trump later put the number at seven boats.

The US operation, dubbed “Project Freedom”, has shaken a fragile ceasefire reached between Iran and the US on April 8 and renewed fears of a return to war.

Iran’s state broadcaster IRIB quoted an unnamed Iranian military commander as saying that Tehran launched an investigation following the US claim of attacks on IRGC vessels.

It said while none of the IRGC vessels was hit, the investigation found that US forces had “attacked two small boats carrying people on their way from Khasab on the coast of Oman to the coast of Iran on Monday”.

The attacks destroyed the boats and killed five civilian passengers, the commander said. The US “must be held accountable for their crime”, the commander added.

There was no immediate comment from the US military.

The violence comes as Trump seeks to reopen the Strait of Hormuz, which Iran has effectively blockaded following the US and Israeli attacks on the country on February 28.

The closure of the vital maritime corridor – through which roughly one-fifth of the world’s energy supplies flow – has sent oil and fertiliser prices surging around the world and prompted fears of a global recession and food emergency.

Iran is now insisting on maintaining control over the Strait of Hormuz and collecting transit fees as reparations for the destruction caused by the US and Israel.

Attacks on UAE, ships in Hormuz

The Iranian military on Monday warned commercial vessels they would “jeopardise their safety” if they attempted to cross the waterway without permission. The military also warned US forces would face attacks if they approached or entered the chokepoint.

Amid the tensions, the United Arab Emirates said Iran launched a drone attack on one of its oil tankers that attempted to transit the strait and said Iranian forces launched 15 ballistic missiles and four drones at its territory.

UAE authorities said the attacks set off a large fire at a major oil refinery in the eastern emirate of Fujairah and wounded three Indian nationals.

A South Korean vessel in the Strait of Hormuz, the HMM Namu, also reported an attack, saying an explosion had caused a fire in its engine room.

Nonetheless, the US military said two US-flagged ships made it through the strait on Monday with the support of navy guided-missile destroyers.

The IRGC denied the claim as “baseless and completely false”, but the global shipping firm Maersk said the US-flagged Alliance Fairfax exited the Gulf via the Strait of Hormuz accompanied by the US military on Monday.

Iran’s Foreign Minister Abbas Araghchi said the events in Hormuz on Monday “make clear there’s no military solution to a political crisis”.

He said in a post on X that peace talks with the US were “making progress” with Pakistan’s mediation and that Washington “should be wary of being dragged back into quagmire by ill-wishers”.

“So should the UAE,” he added. “Project Freedom is Project Deadlock.”

Meanwhile, Trump has renewed his threats against Iran.

He told Fox News Iran would be “blown off the face of the Earth” if they attacked US vessels carrying out Project Freedom.

“We have more weapons and ammunition at a much higher grade than we had before,” he said.

“We have the best equipment. We have stuff all over the world. We have these bases worldwide. They’re all stocked up with equipment. We can use all of that stuff, and we will, if we need it.”

On March 11, the Thai cargo ship Mayuree Naree was struck by two projectiles while crossing the Strait of Hormuz, one of the world’s most important waterways located between Iran and Oman. A fire broke out in the engine room, and while 20 sailors were rescued, three remained trapped inside the stricken vessel. Their remains were found weeks later when a specialised rescue team boarded the vessel, which had run aground on the shores of Iran’s Qeshm island.

At about the same time, a “shadow fleet” of tankers continued to navigate the very same waters safely. Operating with fake flags, disabled signals and unspecified destinations, this covert armada survived because it operates outside the traditional rules of maritime trade.

Iran threatened to block “enemy” ships passing through the Strait of Hormuz – a crucial chokepoint for a fifth of the world’s oil – in the wake of the United States-Israeli war launched on February 28. Soon, navigation through the strait was disrupted amid fears of attacks.

Following a temporary ceasefire on April 8, the United States imposed a full naval blockade on Iranian ports on April 13. Theoretically, traffic through the strait should have come to a complete halt.

However, tracking data reveals a remarkably different reality.

An exclusive Al Jazeera open-source investigation tracked 202 voyages made by 185 vessels through the strait between March 1 and April 15, navigating both under fire and across blockade lines.

The numbers behind the shadows

To understand how the strait operated under extreme pressure, Al Jazeera’s Digital Investigative Unit monitored the waterway daily, cross-referencing vessel International Maritime Organization (IMO) numbers with international sanction lists from the US Office of Foreign Assets Control (OFAC), the European Union, the United Kingdom and the United Nations. An IMO number is a unique seven-digit figure assigned to commercial ships.

Of the tracked voyages, 77 (38.5 percent) were directly or indirectly linked to Iran. Notably, 61 of the ships transiting the strait were explicitly listed on international sanctions lists.

The investigation divided the conflict into three distinct phases to map the fleet’s behaviour:

• Phase 1: Open War (March 1 – April 6): 126 ships crossed the strait, peaking at 30 vessels on March 1. Among these, 46 were linked to Iran.
• Phase 2: The Truce (April 7 – 13): 49 ships crossed during this fragile pause. More than 40 percent of these vessels were tied to Iran, including the US-sanctioned, Iranian-flagged Roshak, which successfully exited the Gulf.
• Phase 3: The US Blockade (April 13 – 15): Despite the explicit naval blockade, 25 ships crossed the strait.

Breaking the blockade

When the US blockade took effect, the shadow fleet adapted immediately.

The Iranian cargo ship “13448” successfully broke the blockade. Because it is a smaller vessel operating in coastal waters, it lacks an official IMO number, allowing it to evade traditional sanction-monitoring tools. The vessel departed Iran’s Al Hamriya port and reached Karachi, Pakistan.

Similarly, the Panama-flagged Manali broke the blockade, crossing on April 14 and penetrating the cordon again on April 17 en route to Mumbai, India.

The investigation uncovered widespread manipulation of Automatic Identification System (AIS) trackers. Vessels such as the US-sanctioned Flora, Genoa and Skywave deliberately disabled or jammed their signals to hide their identities and destinations.

Fake flags and shell companies

To obscure ultimate ownership, the shadow fleet heavily relies on a complex web of “false flags” and shell companies. The investigation identified 16 ships operating under fake flags, including registries from landlocked nations like Botswana and San Marino, as well as others from Madagascar, Guinea, Haiti and Comoros.

The operational network managing these ships spans the globe. Operating firms were primarily based in Iran (15.7 percent), China (13 percent), Greece (more than 11 percent) and the United Arab Emirates (9.7 percent). Notably, the operators of nearly 19 percent of the observed vessels remain unknown.

The toll of a parallel system

Despite the intense military pressure, energy carriers dominated the traffic, with 68 ships (36.2 percent) transporting crude oil, petroleum products and gas. Ten of these tankers were directly linked to Iran. Non-oil trade also persisted, with 57 bulk and general cargo ships crossing during the open war phase, 41 of which were tied to Tehran.

Before the war, at least 100 ships crossed the Strait of Hormuz daily. Today, a staggering 20,000 sailors are trapped on 2,000 ships across the Gulf – a crisis the International Maritime Organization described as unprecedented since World War II.

A shadow Iranian fleet, meanwhile, has been navigating seamlessly as part of a parallel maritime system born from 47 years of US sanctions on Tehran. Washington slapped sanctions on Tehran following the 1979 Islamic revolution that toppled the pro-Washington ruler Shah Mohammad Reza Pahlavi. The two countries have had no diplomatic ties since 1980.

The US naval blockade of Iranian ports and the Strait of Hormuz, in place since April 13, has raised concerns that Iran could run out of crude oil storage capacity and be forced to curb production.

Bloomberg reported analysis on Tuesday from the data and analytics company Kpler suggesting Iran could run out of crude storage in 12 to 22 days if the blockade persists.

Last week, United States Treasury Secretary Scott Bessent claimed that storage capacity at Kharg Island, where most of Iran’s oil is exported, would be full “in a matter of days”.

So how quickly could Iran run out of oil storage, and why does it matter?

What is happening in the Strait of Hormuz?

The Strait of Hormuz is a narrow channel that connects the Gulf to the open ocean. It spans the territorial waters of Iran on its northern side and Oman on its southern side. It is not in international waters.

During peacetime, 20 percent of the world’s oil and liquefied natural gas (LNG) supplies are shipped through the corridor.

Two days after the US and Israel launched their first air strikes in their war on Iran on February 28, Ebrahim Jabari, a senior adviser to the commander in chief of Iran’s Islamic Revolutionary Guard Corps (IRGC), announced that the strait was “closed”. If any vessels tried to pass through, he said, the IRGC and the navy would “set those ships ablaze”.

As the war has dragged on and negotiations have failed to achieve a settlement, Iran has at times in the past two months allowed some “friendly” ships and those that pay tolls to pass. It is currently refusing to allow any foreign-flagged ships, including those previously deemed friendly, to pass until the US lifts its own naval blockade.

Iranian First Vice President Mohammad Reza Aref said on April 19 that the “security of the Strait of Hormuz is not free”.

“One cannot restrict Iran’s oil exports while expecting free security for others,” he wrote in a post on X.

“The choice is clear: either a free oil market for all, or the risk of significant costs for everyone,” he added. “Stability in global fuel prices depends on a guaranteed and lasting end to the economic and military pressure against Iran and its allies.”

Since the US naval blockade on the strait began, the US has opened fire on and taken control of an Iranian-flagged tanker near the Strait of Hormuz while also redirecting vessels on the high seas transporting cargo to or from Iran. Iran’s armed forces have denounced these actions as “an illegal act” that “amounts to piracy”.

The US naval blockade of the strait means that Iran might have to store the oil it produces.

Iran is the third largest oil producer in the Organization of the Petroleum Exporting Countries (OPEC) after Saudi Arabia and Iraq and exports 90 percent of its crude oil via Kharg Island in the Gulf for shipping through the Strait of Hormuz.

What has the US claimed?

The US is eager to curb Iran’s oil revenues, which have risen since Tehran closed the Strait of Hormuz to other shipping. This is the primary motive behind Washington’s naval blockade of Iranian ports.

Iran exported 1.84 million barrels per day (bpd) of crude oil in March and shipped 1.71 million bpd in April, compared with an average of 1.68 million bpd in 2025, according to Kpler.

However, the US naval blockade since mid-April now means that most of its exports are having to be stored instead.

Bessent wrote in an X post on April 22: “In a matter of days, Kharg Island storage will be full and the fragile Iranian oil wells will be shut in.”

“Constraining Iran’s maritime trade directly targets the regime’s primary revenue lifelines.”

How much oil can Iran store?

Iran’s domestic refineries have a production capacity of 2.6 million bpd, according to the energy consultancy Facts Global Energy.

Satellite data show the amount of oil Iran has in storage has risen sharply since the US blockade began, and in the days after the US tightened it, stocks were rising so fast that it appeared Iran had been barely able to export any oil at all.

From April 13 to April 21, data showed that stocks rose by more than 6 million barrels, according to the Columbia Center on Global Energy Policy (CGEP). From April 17 to April 21, the stock increased very rapidly, growing by 1.7 bpd.

As of April 20, the storage tanks at Kharg were about 74 percent full after the island alone had taken on about 3 million extra barrels of oil, the CGEP reported.

Generally, oil companies avoid filling their storage beyond 80 percent capacity to balance safety, emissions control and flexibility.

However, Iran and other oil producing countries have exceeded this limit before, for instance, during the COVID-19 pandemic. In April 2020, Kharg island’s stocks reached close to 90 percent capacity, an all-time high.

Iran also has some crude oil storage capacity in the form of “floating tanks”, or parked ships. About 127 million barrels can be stored in this way, Frederic Schneider, a nonresident senior fellow at the Middle East Council on Global Affairs, told Al Jazeera in an interview on April 14.

Will Iran need to cut oil production?

Muyu Xu, a senior crude oil analyst at Kpler, told Al Jazeera that the blockade could eventually force Iran to cut production.

“However, given there is still available storage capacity onshore (roughly covering 20 days of Iran’s current production), we expect any production reduction to be gradual over the coming week with a higher likelihood of acceleration into May,” she said.

Analysis by CGEP nonresident fellow Antoine Halff echoed this. Halff wrote in an article published by CGEP on Tuesday that it may be some time before the US blockade causes Iran to shut off its production “in a big way”.

However, Halff added, Iran may still choose to halt production “fairly aggressively” but this “would be more by choice than by necessity”.

He explained: “Doing so would have the advantage of providing Iran with relatively ample spare storage capacity after the shutdown and would allow for a smoother restart of operations once conditions permit, and the constraint is relaxed, thus minimising adverse impacts from the blockade on longer-term supply.”

Why does this matter?

Halting oil production risks damaging underground reservoirs by reducing reservoir pressure, allowing water or gas to encroach into producing layers and changing patterns of oil flow. This can make some oil harder or more expensive to recover later, experts said.

Restarting the process of oil production can also be slow and costly, involving repairs of corroded equipment or unclogging pipelines.

Halting production would also cause Iran’s export revenues to drop. However, analysts said that for a few months, Iran can continue to earn revenue from oil that is already in transit at sea.

Kenneth Katzman, former Iran analyst at the Congressional Research Service in Washington, DC, said Iran is not exporting new oil during the US blockade of Iranian ports but Tehran has 160 million to 170 million barrels of oil on ships around the world currently.

The IRGC says the aggression came in response to what it described as the US seizure of an Iranian commercial vessel.

An Iranian gunboat has fired on a container vessel near the coast of Oman, according to a British maritime monitoring agency, in an incident that occurred hours after United States President Donald Trump said he would extend a ceasefire with Iran.

The United Kingdom Maritime Trade Operations (UKMTO) centre said on Wednesday that the ship’s captain reported that the vessel had been approached by a vessel of Iran’s Islamic Revolutionary Guard Corps (IRGC) before shots were fired.

It “has caused heavy damage to the bridge. No fires or environmental impact reported,” the agency added. No casualties were reported, and all crew members were said to be safe.

British maritime security firm Vanguard Tech said the ship was sailing under a Liberian flag and had been informed it had permission to pass through the Strait of Hormuz, one of the world’s most strategically important waterways.

Iranian news agency Tasnim, however, said the vessel had ignored warnings issued by Iran’s armed forces.

The incident followed a warning from the IRGC’s Khatam al-Anbiya Central Headquarters after what it described as the US seizure of an Iranian commercial ship in the Sea of Oman, the IRNA news agency reported.

It accused Washington of violating the ceasefire and carrying out “armed piracy” after allegedly firing on the Iranian vessel and disabling its navigation systems.

Trump extends ceasefire

Trump earlier announced he would delay a planned military attack on Iran after requests from Pakistan’s army chief Asim Munir and Prime Minister Shehbaz Sharif.

Writing on Truth Social, Trump said the decision was made because Iran’s government was “seriously fractured” and needed time to present a unified position.

“We have been asked to hold our Attack on the Country of Iran until such time as their leaders and representatives can come up with a unified proposal,” he wrote.

He added, however, that the US naval blockade of the Strait of Hormuz would remain in place and said the military had been ordered to stay “ready and able”.

The announcement marked a shift from comments made a day earlier, when Trump said it was “highly unlikely” he would extend the truce beyond Tuesday.

‘Positive and negative signals’ from Tehran

Al Jazeera’s Tohid Asadi, reporting from Tehran, said Iranian officials were sending mixed messages over the ceasefire and the prospects for negotiations.

“Tehran is saying they won’t negotiate under imposed terms and conditions … when we compare the initial 10-point and 15-point proposals by the Iranians and Americans, we can understand that the two sides are poles apart,” he said.

“The atmosphere is also clouded by this mistrust in Tehran towards the United States, as well as the simultaneous military rhetoric related to a potential failed negotiation … It is a warning that another round of confrontation may be ahead.”

He said Iran still viewed the Strait of Hormuz as a key source of leverage in any talks.

“It’s trying to exercise authority over the ships and vessels transiting this strategically significant chokepoint,” he said.

Asadi added that Iranian officials framed their regional position as based on mutual security. “Iranians are saying that the basis of their foreign policy behaviour, particularly when it comes to Israel, is security for all versus security for none,” he said.