Thirty-three Senate Republicans sent a letter on Monday to President Joe Biden stressing that he is legally required to provide Congress with the chance to review any agreement with Iran — even if it is not submitted for ratification as a treaty.

The letter, prompted by recent reports that the U.S. and Iran are on the verge of re-entering the 2015 Joint Comprehensive Plan of Action, emphasizes that, under the 2015 Iran Nuclear Agreement Review Act, Biden must submit any nuclear deal with Iran for Congress’ review within five days of concluding the agreement. INARA then bars the administration from withdrawing any sanctions on Iran during a subsequent review period.

The senators, led by Sen. Ted Cruz (R-TX) wrote that they “are committed to providing availability, assistance and resources so you can fully meet these mandates.” 

“We also write to emphasize that we are committed to using the full range of options and leverage available to United States Senators to ensure that you meet those obligations, and that the implementation of any agreement will be severely if not terminally hampered if you do not,” the letter reads.

INARA was passed with substantial bipartisan majorities in both chambers of Congress. Former President Barack Obama had initially considered vetoing the legislation, until it became apparent that Congress could override his veto.

In their letter, the senators also urge Biden to submit the agreement for ratification as a treaty. The JCPOA was not submitted and would not have had sufficient support to be ratified.

“[A] genuinely robust nuclear agreement with Iran would be compelling enough to secure assent from two-thirds of the Senate – and the only reason not to present it for a resolution of ratification is that it is too weak to pass muster,” the letter continues. “Any agreement related to Iran’s nuclear program which is not a treaty ratified by the Senate is subject to being reversed, and indeed likely will be torn up, in the opening days of the next presidential administration, as early as January 2025.”

Notable signatories to the letter include the top Republicans on the Senate Foreign Relations, Armed Services and Intelligence Committees, Sens. Jim Risch (R-ID), Jim Inhofe (R-OK) and Marco Rubio (R-FL).