Lawmakers and pro-Israel groups have issued calls for United States President Donald Trump to ask Congress to review a recent memorandum of understanding (MoU) designed to end the US-Israeli war with Iran.

They cite the Iran Nuclear Agreement Review Act (INARA) as a precedent. Passed in 2015, the law says any agreements with Iran related to its nuclear programme must be submitted to Congress for review and a possible vote of disapproval.

The act came into effect when former US President Barack Obama was negotiating the now-defunct Joint Comprehensive Plan of Action (JCPOA) with Iran, and it remains on the books today.

US Senator Lindsey Graham was among the first lawmakers to invoke the act after this week’s memo was announced.

“Under our law, any nuclear deal with Iran will be sent to Congress for review and a vote. I look forward to reviewing the final product,” Graham, a longtime Iran hawk, wrote in a social media post on Sunday.

Critics, including some Democrats and pro-peace groups, have questioned the newfound interest in Congress asserting its powers, after Republicans repeatedly flouted the legislature’s authority during the war itself.

Some see the push as an effort to give the memorandum greater legitimacy, as Trump comes under fire for its terms. Others question whether Iran hawks are invoking INARA to push for a return to war.

Here’s what to know about the debate:

What does the law say?

INARA creates requirements for any agreement between the US and Iran “related to the nuclear program of Iran”, no matter “the form it takes” or whether the agreement is legally binding.

Ahead of its passage in 2015, it was championed by bipartisan opponents of the JCPOA. That deal, which saw Tehran curtail its nuclear programme and submit to regular inspections in exchange for sanctions relief, was subsequently subject to provisions of the law.

The law requires the president to submit the text of any agreement he strikes with Iran to Congress within five days, along with any related materials. That triggers a 30-day approval period.

During that period, members of Congress can choose to pass a joint resolution of disapproval to scuttle the deal.

Still, such a resolution would be subject to the presidential veto. A successful disapproval resolution would therefore require a two-third majority from both chambers to override any vetoes, an extremely high bar.

During the congressional review period, the president “may not waive, suspend, reduce, provide relief from, or otherwise limit the application of statutory sanctions with respect to Iran under any provision of law or refrain from applying any such sanctions pursuant to [the] agreement”, the law states.

Those terms could limit this week’s memorandum, as it includes sanctions relief for Iran.

Does INARA apply to the memorandum of understanding?

Trump has suggested he was open to sending the US-Iran memorandum to Congress, telling reporters earlier this week: “I like the idea. I mean, who wouldn’t approve it?”

But his administration has not yet done so. Administration officials have also not articulated a stance on whether or not they believes the memo is subject to the law. Trump, after all, has frequently denied needing congressional approval for his actions against Iran.

This week’s memorandum opens the Strait of Hormuz, lifts the US blockade on Iran’s ports, and halts fighting on all fronts, including in Lebanon.

It also immediately lifts US sanctions on Iran’s fossil fuel industry, while launching negotiations on the future of Iran’s nuclear programme, among other issues.

As part of the deal, both countries agree to maintain their nuclear “status quo” during ongoing negotiations, and Iran commits to diluting its highly enriched uranium “on site”, with details to be determined during the negotiations.

While Trump has yet to acknowledge INARA’s authority, legal experts from across the ideological spectrum have argued that his memorandum is subject to the law.

Tess Bridgeman, a legal adviser for the Obama White House, wrote that the law applies to “this new MoU, and any future final agreement that might be negotiated in the coming months”.

But in an article published in the policy forum Just Security, she argues that INARA should be repealed, so as to not impede the ongoing diplomacy.

“INARA was never an appropriate way for Congress to engage on Iran’s nuclear program, and that is even more true today,” Bridgeman wrote.

Jack Goldsmith, a Harvard Law School professor and fellow at the conservative American Enterprise Institute, also believes that the memorandum should trigger an INARA review.

He also notes that Trump’s commitment to “immediately” lift sanctions on Iran’s oil industry appears to run afoul of INARA.

“I don’t think the president has the authority under domestic law to issue these waivers,” Goldsmith wrote on the Executive Functions website.

Still, he anticipates that neither Congress nor the judicial branch will confront Trump over the issue.

Will Trump comply with the law?

Trump’s second term has been defined by a broad interpretation of presidential power.

His administration has previously flouted the US Constitution’s provision that Congress alone has the power to declare war.

Trump has maintained that Iran represented an “imminent threat” to the US, which allowed him to launch defensive strikes without congressional approval.

Administration officials have also argued that the president is not beholden to the legal requirement that he gain congressional approval within 60 days of launching an attack. The war, which started on February 28, has lasted nearly three and a half months.

In an interview with the news outlet Axios on Thursday, Trump mused that the war taught him there are “no limits” to his power as president.

It remains unclear if Trump will change course and embrace the congressional collaboration required for diplomacy under INARA.

In her article, Bridgeman argued that Trump could flout the law in whole or in part, particularly when it comes to the immediate sanctions relief, because his party controls Congress.

Goldsmith, meanwhile, pointed out that the administration could also try to argue that the memorandum only sets out terms to reach an eventual agreement and is not an agreement itself.

While Goldsmith believes that argument is faulty, he noted that “it’s doubtful that any institution will make the president comply with INARA”.

A newfound interest in congressional oversight?

Several pro-Israel groups, including The Jewish Institute for National Security of America (JINSA) and the American Israel Public Affairs Committee (AIPAC), have been among the loudest voices calling for congressional involvement in the deal.

Since the outset of the war, JINSA defended Trump’s claims that Iran represented an “imminent threat” to the US, thereby granting him authority to attack without congressional approval.

However, the group also called on Congress to pass an Authorisation for the Use of Military Force (AUMF) to bolster his actions.

Congress, however, has repeatedly sought and failed to re-assert over its authority to send the US to war.

Since February, several war powers resolutions have been introduced to halt US action against Iran and force Trump to engage with Congress.

Initially, several Democrats backed by AIPAC, including Senator John Fetterman, Representative Jared Moskowitz and Representative Josh Gottheimer, broke from the party to oppose those efforts.

Moskowitz and Gottheimer eventually shifted their stances in March to vote in favour of one of the resolutions. But Congress has yet to pass a bill with enough votes to overcome an eventual Trump veto.

Meanwhile, Republicans in both the House and Senate chose to ignore a 60-day deadline in May that legally required Trump to get congressional approval for continued military operations — or stop fighting.

In a statement on Friday, Democratic Senator Chris Van Hollen characterised the Republican embrace of INARA as evidence of hypocrisy.

“Republican senators who were AWOL [absent without leave] regarding their constitutional duties around STARTING the war against Iran all of a sudden demand that Congress play a role in STOPPING the war,” he wrote.

“A whole lot of warmongering going on.”