Washington, DC – The United States Senate will vote later this week on bills to block a $20bn arms deal with Israel, an effort advocates say will set a precedent in congressional efforts to halt weapons transfers to the US ally.

Senator Bernie Sanders – a progressive independent who caucuses with the Democrats – introduced the measures, known as Joint Resolutions of Disapproval (JRDs), in September and announced on November 13 that he will bring them to the Senate floor for a vote this week.

The effort is unlikely to pass in the mostly pro-Israel chamber, but it has been garnering support from rights groups and a growing number of Democratic lawmakers.

Hassan El-Tayyab, an advocacy organiser at the Friends Committee on National Legislation, a Quaker social justice group, described the upcoming vote as “historic”.

He said the resolutions send a message to President Joe Biden, his successor-in-waiting Donald Trump and Israeli Prime Minister Benjamin Netanyahu that the “status quo is unacceptable”.

“Just the fact that this is happening is already sending that political signal that it’s not business as usual,” El-Tayyab told Al Jazeera.

He added that congressional pressure could alter the behaviour of the US administration and its Israeli allies.

The letter

The expected vote will come about two weeks after the Biden administration said it had not made an assessment that Israel is blocking humanitarian aid to Gaza – a conclusion that contradicted the findings of humanitarian groups.

Secretary of State Antony Blinken and Pentagon chief Lloyd Austin had sent a letter to Israeli leaders on October 13, threatening “consequences” under US law if Israel did not take specific steps to improve the humanitarian situation in Gaza within 30 days.

US law bans military assistance to countries that block Washington-backed humanitarian aid.

Continuing US military aid to Israel after the Blinken-Austin deadline – despite warnings by United Nations experts that famine was already spreading across Gaza – highlighted Biden’s uncompromising support for Israel.

El-Tayyab said the administration’s “cynical” decision makes Congress’s oversight role and Sanders’s resolution all the more important.

“Congress isn’t a passive bystander. It’s a co-equal branch of government that shares responsibility for what’s happening in Gaza,” he said.

In a statement announcing that he intends to force a vote on the resolution, Sanders said there was “no longer any doubt” that Israel is violating international and US law.

“As horrific as the last year has been, the current situation is even worse. Today, Israel continues to restrict the flow of food and medicine to desperate people,” the senator said.

“Tens of thousands of Palestinians face malnutrition and starvation. The volume of aid reaching Gazans is lower than at any time in the last year.”

What are JRDs?

Under US law, the executive branch can authorise weapons sales to foreign countries, but Congress has de facto veto power over the issue.

Lawmakers can introduce a measure to block a given sale – a JRD – under the Arms Export Control Act. For the resolution to become law, it would have to pass in the Senate and the House of Representatives and be signed by the president.

Since a JRD is almost by nature in opposition to White House policy, presidents are likely to block the proposed legislation, but Congress can override the presidential veto with a two-thirds majority in both chambers.

Sanders has introduced several resolutions that would block the sale by the US of tank and mortar rounds, direct attack munitions (JDAMs), F-15 fighter jets and other weapons.

Some of the JRDs blocking munition sales to Israel are backed by Democratic Senators Peter Welch, Jeff Merkley and Brian Schatz.

Senator Elizabeth Warren also voiced support for the effort, invoking the Biden administration’s failure to hold Israel accountable for blocking humanitarian aid to Gaza after the Blinken-Austin letter.

“The failure by the Biden administration to follow US law and to suspend arms shipments is a grave mistake that undermines American credibility worldwide,” Warren said in a statement last week.

“If this administration will not act, Congress must step up to enforce US law and hold the Netanyahu government accountable through a Joint Resolution of Disapproval.”

While Congress has voted previously on amendments about conditioning aid to Israel, a Senate vote on a JRD concerning the US ally would be the first of its kind.

Support for effort

More than 110 advocacy organisations, including Amnesty International USA, the Arab American Institute and Human Rights Watch, have issued a joint statement endorsing the JRDs.

“The joint resolutions of disapproval would suspend particular transfers of types of weapons that the Israeli government has used in strikes that have killed thousands of civilians, including aid workers and journalists, in Gaza over the last year,” the groups said in the statement.

Israel’s US-backed war on Gaza has killed more than 43,800 Palestinians and brought the territory to the verge of starvation. The intensifying Israeli offensive in Lebanon has also destroyed large parts of the country and killed more than 3,480 people.

The American-Arab Anti-Discrimination Committee (ADC) said Israel “should not receive one dollar more in US support” because of its abuses.

“The Biden Administration has lost all credibility when it comes to its complicity and participation in Israel’s genocide, going so far as to completely ignore US law,” the group said in a statement.

“It is long past time for Congress to step in and do what President Biden, Secretary Blinken, and Secretary Austin will not – enforce US law and say no more weapons for Israeli genocide.”

The Council on American-Islamic Relations (CAIR) echoed that statement.

“With undeniable proof of Israel’s war crimes and the deliberate obstruction of humanitarian aid, our government continues to sell billions in offensive weapons to Israel,” CAIR’s government affairs director, Robert McCaw, said in a statement.

“This unconscionable support for genocide perpetuates violence and suffering. With the Senate vote next week, we have a critical opportunity to stop these arms sales.”

Pro-Israel response

Sanders’s push may be a long-shot effort, but pro-Israel groups have noticed it and are lobbying against the resolutions.

The American Israel Public Affairs Committee (AIPAC) urged its supporters to contact their senators to reject the resolutions.

“Weakening Israel’s security as it’s engaged in a seven-front war against common enemies is dangerous for America and the Jewish state,” the group told supporters in an email.

The Democratic Majority for Israel (DMFI), a pro-Israel advocacy group focused on Democratic officials, issued a similar message.

“Senator Bernie Sanders and others plan to put forward legislation to block military aid to Israel next week, even as Israel is under attack, and the Biden Administration confirmed that Israel is adhering to the standards set by the United States for humanitarian aid into Gaza,” the DMFI said.

“We must do everything we can to stop him.”

El-Tayyab dismissed such criticism, underscoring that the legislative push only aims to block offensive weapons to Israel.

“There is no military solution to the conflict in Gaza – only a diplomatic one that addresses root causes of violence,” he told Al Jazeera.

“Instead of sending more weapons, Congress and the administration should leverage military aid with Bibi [Netanyahu] and the Knesset to finally get them to accept a ceasefire deal in Gaza and Lebanon. And that, I think, is a far better strategy to secure Israel’s defence and protect Palestinian human rights.”