But questions about why the deal is only happening now, when some of the prisoners have been in jail for years, continue to linger.

US Secretary of State Antony Blinken has said that the deal is “not linked” to any other aspect of Washington’s Iran policy, with the focus only on freeing US citizens and residents wrongfully detained in Tehran. But Iran’s Ministry of Foreign Affairs has said that an integral part of carrying out the deal now was access to $6bn of its funds frozen in South Korea.

Prisoner swap blackmail?

Some critics have charged the US with giving into Iranian “blackmail” by agreeing to the deal.

US Republican Senator Tom Cotton accused the country’s President Joe Biden of a “craven act of appeasement” that would “embolden” Iranian leaders, in a statement earlier in August.

Iran’s economy is currently ailing. According to the World Bank, the country faces intensified climate change challenges, including severe droughts, which could restrict agricultural output.

The war in Ukraine has also raised Iran’s import bill, putting a strain on government finances.

“It’s clear that Iran is expecting the funds in South Korea to become accessible so that they can benefit and revamp their economy, which is currently struggling. But this money is also their own. It’s not that the US is giving them money,” Roxane Farmanfarmaian, academic director and lecturer in international politics at the University of Cambridge specialising on Iran, told Al Jazeera.

“I also think it’s a bit disingenuous to say that in this prisoner swap deal, Iran is the only one that’s blackmailing here. I’m not saying Iranian law is practised in an appropriate way, but since the US withdrew from the 2018 JCPOA [Joint Comprehensive Plan of Action] nuclear deal and placed Iran under extraordinary sanctions and froze all its funds when Tehran had been complying with the deal, the entire US approach towards Iran has also involved a bit of blackmailing,” she added.

Iranian human rights lawyer and former head of public interest law at Oxford University Kaveh Moussavi also thinks the US-Iranian deal has come about because the Biden administration has a vested interest in making sure war does not break out in yet another part of the world, and is apprehensive about Iran’s relations with Russia.

“The West is working flat out to supply the ammunition needed by Ukraine, while Russia has run out and they’re begging Iran and North Korea to supply them with drones, shells and mortars. The US is aware that Tehran is very heavily invested in the survival of the Russian regime and is keen to change that narrative and also ensure Tehran is at peace with its other neighbours in the Middle East,” he told Al Jazeera.

Since Russia invaded Ukraine last February, Moscow and Tehran have gotten closer.

But while Iran has acknowledged supplying drones to Russia before the beginning of the Ukraine conflict, it has rejected US accusations that it has sent hundreds of drones to Russia since the beginning of the war.

Dissent towards the deal

Tehran has said the prisoner exchange deal will be implemented once the frozen assets arrive at a bank account in Qatar’s central bank.

But not everybody in the US is happy with the deal, particularly family members of a US permanent resident who has not been included.

“My father Shahab Dalili, a US permanent resident and citizen of Iran, continues to languish in prison in Tehran. I have not been given any explanation regarding why he hasn’t been released. The US government says it is because my father has not been designated as ‘unlawfully detained’. It has been seven years and I need the American government to act responsibly,” Darian Dalili, Shahab’s son, told Al Jazeera.

Shahab Dalili, now 60 years old, was arrested in April 2016 while on a visit to Tehran for his father’s funeral. Iranian authorities charged him with “aiding and abetting a hostile nation” which in his case was “aiding the US”, according to Darian Dalili.

“Since then, my father has been imprisoned at Tehran’s Evin prison, known for human rights abuses. While he is no longer in solitary confinement, the living conditions in prison are still bad. The beds that they have have been described to me, not by him, but by others who have been there, as coffins. But my father remains strong. He spends his time reading a lot, taking walks in the prison yard. He hasn’t given up yet, giving us hope to continue fighting for his release,” Dalili said.

Day 6 of our sit-in outside @StateDept.
Pls @SecBlinken, implement the Levinson Act & designate Shahab “unlawfully detained.” He too deserves to be included in the deal with #Iran to bring Americans home.#FreeShahabDalili@POTUS @brett_mcgurk @JakeSullivan46 @RepWexton pic.twitter.com/bLWp2RusaK

— Free_Dalili (@Shahab_Dalili) August 16, 2023

Asked by journalists why Shahab Dalili was left out of the prisoner exchange deal, Secretary Blinken said he could not reveal details of individual cases, but said that the US was “constantly reviewing” cases of unlawful detentions in Iran.

Mohammad Marandi, a professor at the University of Tehran, told Al Jazeera that “the US and its allies always claim everyone held in Iran is innocent, but it’s very difficult to imagine the US being so innocent.”

“Even the US government admits that the Iranians held in their prisons never harmed the US,” he added, highlighting the Iranian prisoners held in the US, who are believed to have been accused of violating sanctions on Iran.

How will the deal change US-Iran relations?

Meanwhile, Secretary Blinken has added that nothing about the deal changes the US’s overall approach towards Iran.

“We continue to pursue a strategy of deterrence, of pressure and diplomacy. We remain committed to ensuring that Iran never acquires a nuclear weapon. We continue to hold the regime accountable for its human rights abuses, destabilising actions in the region, funding of terrorism, provision of drones to Russia for its use in war against Ukraine, among many other offences. We’ve been clear that Iran must de-escalate, to create space for future diplomacy,” Blinken told journalists on August 15.

Farmanfarmaian agrees that at this stage, the deal is mainly for the US to get its citizens out of prison and for Iran to get its money.

“It doesn’t have huge implications for other aspects of US-Iran relations like the nuclear deal, which has both economic and enrichment issues associated with it,” she said.

The US unilaterally withdrew from the nuclear deal with Iran in 2018, and imposed sanctions on Iran.

Farmanfaraian did, however, highlight that the fact that the US and Iran are now talking and negotiating through this deal is significant.

“It means that the direct lines of communication are open. So unlike the JCPOA renegotiations which needed European delegates to also conduct the talks, these negotiations appear much more direct. Obviously, countries like Qatar and Oman were involved, but it does seem to be that there is a lot of closer negotiation in the hallways,” she said.

However, Moussavi thinks “it is inconceivable” that Iran and the US will be able to have a normal relationship on the back of the prisoner swap deal.

“Such prisoner swaps might normalise relationships for a little while but how many times has Iran tried to restore diplomatic relations with countries like Britain in this manner? Sanctions on Iran are in place for a reason,” Moussavi said. “I don’t see this prisoner deal changing future relations to a great extent, with the US.”