Two weeks before a crucial diplomatic deadline, newly victorious Republicans in Congress are plotting to derail one of Barack Obama’s few remaining chances for a second-term policy legacy: a nuclear deal with Iran.

The Obama administration’s interim agreement with Tehran expires on Nov. 24. But Senate Republicans don’t plan to wait until they take power in January to rattle the nuclear talks. On Thursday, a day after returning to Washington, they will seek a vote on legislation requiring that Congress approve any deal.


Democrats, who still control the Senate, are likely to quash the move. But it’s an early illustration of Republican plans to confound the president’s nuclear diplomacy, which the GOP sees as dangerously weak toward Tehran’s anti-American Islamic regime.

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“The Hill has a lot of power to make things miserable for the president,” said Mark Dubowitz, executive director of the Foundation for the Defense of Democracies and a critic of the nuclear talks who consults closely with Congress on Iran legislation.

The White House has spent months beating back congressional action on Iran, including toughened sanctions on the longtime U.S. foe, which is presumed to be pursuing a nuclear weapon. New pressure on the Iranians could drive them from the negotiating table, say Obama officials — and lead the United States to war.

Though some Democrats support such measures — a proposal threatening stiffer sanctions won 60 Senate co-sponsors in the last Congress, including 15 Democrats — Senate Majority Leader Harry Reid has kept them bottled up. “That situation will be different in the new Congress,” said a Republican aide, noting that the incoming Senate leader, Mitch McConnell, won’t comply with White House pleas the way Reid did.

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The role Republicans play will depend on the course of the ongoing nuclear talks. An interim deal struck in Geneva last November by the U.S. and five other world powers — Russia, China, France, Great Britain and Germany — expires on Nov. 24. That deal froze the progress of Iran’s nuclear program in return for limited sanctions relief.

Over the weekend, Secretary of State John Kerry and other U.S. officials met with Iranian officials in Oman. Their goal is to strike a long-term deal lifting sanctions in return for restrictions that would prevent Tehran from easily building an atomic bomb.

But the Oman session seemed to achieve little; a planned press conference with the participants was canceled. “As best I can tell, [there was] no progress,” said Gary Samore, a former Obama White House aide who handled the Iranian nuclear portfolio and is now president of United Against a Nuclear Iran.

Obama officials say it’s still possible that a long-term deal will be reached by Nov. 24. But Samore and other experts expect the interim deal, which was already extended once in July, will be extended again into 2015.

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Either way, a Republican Congress will have its say come January.

“I want to start [the Iran] discussion Thursday, and hopefully we’ll bring the bill up,” said Republican Sen. Lindsey Graham of South Carolina. “But in the event we do not, I hope Sen. McConnell will make sanctions and the [Iran Nuclear Negotiations Act] must-dos in the new Congress.”

Introduced in July, the Iran Nuclear Negotiations Act would require an up-or-down vote by Congress on any final agreement with Iran. Many Republicans expect any deal to make too many concessions to Iran, and agree with Israeli Prime Minister Benjamin Netanyahu that the Iranians should be barred from maintaining a uranium enrichment program — something Tehran almost certainly will not agree to.

A no vote wouldn’t actually void an Iran pact, however, because a nuclear deal wouldn’t constitute a formal treaty and therefore would not require Senate ratification. But if the Senate were to vote against a nuclear agreement, the legislation would re-impose any sanctions suspended by such a deal. If such a move were to survive a presidential veto, it would effectively kill an agreement with Iran.

If the interim nuclear deal is extended with few or no new concessions by Iran, sources say Republicans are likely to take up legislation similar to a Senate bill sponsored last year by Foreign Relations Committee Chairman Robert Menendez and Sen. Mark Kirk, the one that drew 60 co-sponsors. That bill threatened new sanctions should Iran violate the interim agreement, or if it abandons the negotiations.

If the interim deal is extended with few or no new concessions by Iran, Republicans are likely to take up legislation similar to a bill sponsored last year by Foreign Relations Committee chairman Robert Menendez and Sen. Mark Kirk.

“If it’s just a simple extension with a couple of bells and whistles, like they did [in July], I expect Congress to move forward with a new bill similar to Menendez-Kirk,” said Dubowitz. “For the administration to actually get an extension without that they would have to come back with a partial deal — but a meaningful partial deal.”

Republicans say they have other ways to complicate Obama’s deal making with Tehran, including by denying funding to offices that would implement any deal with the Iranians.

Even before last week’s Republican electoral sweep, tensions were growing between the White House and the Hill over Iran policy. Members of both parties have long complained that Obama officials, who regularly brief Hill leaders privately about the Iran talks, have provided them with only limited and opaque information about the talks. Last week’s revelation by The Wall Street Journal that Obama recently sent a secret letter to Iran’s Supreme Leader, Ayatollah Ali Khamenei, left many members fuming.

The friction also spiked after The New York Times reported in mid-October that Obama officials were designing an Iran deal that would rely heavily on executive authority to suspend many of the U.S.-imposed sanctions that have stunted Iran’s economy. Administration officials say the president has that power, although only Congress can permanently lift sanctions it has passed.

A State Department spokeswoman called the premise of the Times story “wrong.” But a Democratic staffer who has been briefed by senior officials called the idea “very real.” And senior Republicans already concerned that Obama would cut a soft deal with Iran are determined not to be sidelined.

A senior administration official argued that Secretary of State John Kerry would not cut a deal with Iran that couldn’t be defended against critics, noting that any comprehensive agreement would also require the approval of America’s negotiating partners.

As the administration has in the past, the official also again raised the idea that opponents of a deal with Iran were in effect choosing a path of dangerous confrontation. “You’re going to vote no — what’s that a vote for? So you think we should go to war?”