GOP Senators Warn Iran’s Leaders on Nuclear Deal

Forty-seven lawmakers say Congress could nullify any deal once Obama leaves office.

President Barack Obama on Monday sharply criticized an open letter by 47 Senate Republicans warning Iran’s leaders that any agreement between the White House and Tehran on nuclear weapons could be quickly nullified or changed once Mr. Obama leaves office.

The lawmakers were effectively aligning themselves with Iranian hardliners who oppose an international nuclear deal, Mr. Obama said.

The letter, which was signed by Senate Majority Leader Mitch McConnell (R., Ky.) and a number of top committee chairmen, came as a major new complication in a debate over international nuclear talks that face a March 31 deadline.

Senators said that, unless approved by Congress, any agreement between world powers and Iran would be seen by GOP lawmakers as an executive agreement between Mr. Obama and Iran’s Ayatollah Khamenei and could lapse when a future administration takes over, or undergo modifications by lawmakers.

The senators noted that Mr. Obama will leave office in January 2017, while “most of us will remain in office well beyond then—perhaps decades.

“The next president could revoke such an executive agreement with the stroke of a pen and future Congresses could modify the terms of the agreement at any time,” said the letter.

Mr. Obama criticized the Republican outreach.

“I think it’s somewhat ironic to see some members of Congress wanting to make common cause with the hardliners in Iran,” the president told reporters in the Oval Office. “It’s an unusual coalition.”

Mr. Obama said his focus was on getting to an agreement with Iran that would allow the country to develop a nuclear energy program while ensuring that it could not be weaponized.

“I think what we’re going to focus on right now is actually seeing whether we can get a deal or not,” he said. “Once we do—if we do—we’ll be able to make the case to the American people.”

Iranian Foreign Minister Javad Zarif said that world relations are based on international obligations and commitments, “not based on the domestic U.S. laws.”

Any future annulment of U.S. commitments would be “an obvious violation of international laws, particularly if these commitments lie within the framework of a U.N. Security Council resolution and are the result of negotiations and agreement with five other countries which are permanent members of the Security Council,” Mr. Zarif said.

Those signing the letter included Senate Armed Services Committee Chairman John McCain (R., Ariz.), as well as 2016 GOP presidential hopefuls Sens. Marco Rubio of Florida, Rand Paul of Kentucky and Ted Cruz of Texas.

In Tehran, one expert predicted the letter wouldn’t sway Iran’s negotiators, who likely view it as a “disruptive trick,” rather than a threat with an impact.

“This is just a disruptive, radical move in the middle of the talks by some of their extremists who are against Iran and the system” of the Islamic republic, said Hamid Reza Jalaeipour, a political analyst in Tehran.

He said the letter was a reaction to positive progress on the nuclear talks and to the fact that Israeli Prime Minister Benjamin Netanyahu ’s congressional address last week had not turned out to be a “game-changer” in scuttling a nuclear deal.

Key Democrats on Capitol Hill rebuked the GOP senators, saying it gave leverage to Iranian negotiators while hurting the U.S. position.

“Let’s be very clear, Republicans are undermining our commander in chief while empowering the ayatollahs,” Senate Minority Leader Harry Reid (D., Nev.) said, describing it as a “hard slap” at both the White House and the country’s international allies who are also party to the talks.

Rep. Adam Schiff (D., Calif.), the top Democrat on the House Intelligence Committee, said during an appearance on MSNBC that he was “appalled” by the letter. “On an issue of this seminal importance while sensitive negotiations are going forward, for these senators to interfere in this way, it’s really unthinkable,” Mr. Schiff said.

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