A pro-peace lobby said Thursday that Republican senators are about to push an initiative that could effectively scupper any nuclear deal with Iran.

The Friends National Committee on Legislation said that Sens. Bob Corker (R-Tenn.) and Lindsey Graham (R-S.C.) will seek to advance legislation they drafted that would grant lawmakers the final say on any accord with Tehran.

“Since it’s widely expected that the majority of Congress would reject any nuclear deal reached with Iran, a vote would block a deal from coming into effect,” FCNL Executive Secretary Diane Randall said.

The historically Quaker anti-war lobby warned that a vote could be “devastating” to the historic detente between the US and Iran by “flagrantly” infringing upon prior American commitments.

“Iran could respond by withdrawing from the agreement and restarting elements of its nuclear program that are now rolled back under the interim deal,” Randall said.

She also pointed out that any final say on permanent sanctions relief already depends on the approval of the legislative branch, but “this new proposal would force Congress to react to the deal before it’s been fully implemented.”

Despite skepticism over the deal, it’s unclear whether the Graham-Corker legislation, if introduced and passed by Congress, would receive a veto-proof majority. Hawkish Democrats have increasingly shown a willingness to allow the Obama administration wiggle room in its pursuit of diplomacy with Iran. Ten Senate Democrats, led by Sens. Bob Menendez (D-N.J.) and Chuck Schumer (D-.N.Y.) told the administration that they would temporarily relinquish their efforts to slap Iran with new sanctions.

“In acknowledgement [sic] of your concern regarding congressional action on legislation at this moment, we will not vote for this legislation on the Senate floor before March 24,” the ten senators said.

On Jan. 22, Politico reported that Senate Republicans were keen on advancing both the Graham-Corker legislation and the sanctions bill that Democrats want to shelve until next month.

“We’re in such a much stronger place requiring congressional vote on any final deal – that to me is an even stronger place for us to be,” Corker, the chair of the Senate Foreign Relations Committee said.

Deputy Secretary of State Antony Blinken on Jan. 21 told Corker’s committee that the administration was concerned Congressional approval of the deal would infringe upon presidential authority, as The Sentinel noted.

“There’s a concern that this could set a precedent for future executive branch action,” Blinken said.“The knowledge that there would be, very early on, this kind of vote, in our judgment, could undermine the credibility of the commitments we would make in the context of negotiations,” he added.

The high-ranking envoy also noted that the administration believed the move to hinge temporary sanctions relief on Congressional approval would note give “the Iranians time to demonstrate to you, and to us, that they’re making good on their commitments.”

On Jan. 27, however, Corker claimed on Twitter that he wanted Congress’ approval on the result of negotiations so that any agreement would “stand the test of time.”