WASHINGTON — The US Senate will take up a 10-year extension of American sanctions on Iran after the US House overwhelmingly passed the measure, Senate Majority Leader Mitch McConnell said Thursday.

With the sanctions, lawmakers would signal to President-elect Donald Trump that whatever his foreign policy, they intend to take a hard line against Tehran. For his part, Trump has criticized the controversial Iran nuclear deal and promised on the campaign trail to renegotiate it. That's a complex proposition, as it involves seven nations and was endorsed by a UN Security Council resolution.

"This bipartisan bill, which provides the basis for any sanctions which may be re-imposed on Iran, is critical given the belligerent behavior exhibited by Tehran since the signing of the Joint Comprehensive Plan of Action," McConnell said. "I expect we'll pass it on an overwhelming bipartisan basis here too.

Supporters of an extension of the Iran Sanctions Act argue that extending it ensures that a "snap back" of sanctions adds leverage for Iran to abide by the Joint Comprehensive Plan of Action (JCPOA), particularly as it exerts influence in Iraq, sends arms to rebels in Yemen and supports the group Hezbollah.

The White House has argued the extension is unnecessary because it has the ability to punish Iran under the JCPOA for any breaches, but there has been no veto threat. Tehran, however, has argued renewing the sanctions would nullify the JCPOA.

The extension applies to longstanding American sanctions that were intended to deter Iran's illicit weapons programs and ballistic missiles development. Unless the Senate and president Obama approve an extension, they will expire at year's end.

Senate Foreign Relations Chair Bob Corker, R-Tenn., told reporters Wednesday that next year he would introduce still more punitive measures against Iran, predicting he would have more support from more Democrats than he would have under a Democratic president.

"There is a sense of freedom by many of them to push back against missile testing, conventional weapons purchases, those kinds of things," Corker said.

The Senate Foreign Relations Committee's top Democrat, Sen. Ben Cardin, of Maryland, said that beyond the extension, "Congress is prepared to take a stronger role" to ensure Iran complies with the terms of the Iran nuclear deal and to respond to Iran's "non-nuclear nefarious actions."

Though the JCPOA faced opposition, Cardin said lawmakers felt that "it was much better than the military option" to end Iran's nuclear program. In assessing the deal, he said, Trump should consult with the signatories about its worth, suggesting it would be tough tear up without damaging US relations with those counties.

"I think the president should talk with the coalition partners, the group involved with the JCPOA," Cardin said. "Go talk to our European allies, because they are more aligned with us. Talk to the French, talk to the Germans, talk to the Brits. Then talk to Russia, China and ultimately Iran."

For its part, Germany will try to ensure the JCPOA survives, Reuters reported Wednesday. "You can be sure that we will try to convince this (Trump) administration that what we agreed one-and-a-half years ago and have since implemented, both in words and deeds, remains, from our point of view, the right policy," a foreign ministry spokesman reportedly said at a news conference.

On Monday, 76 foreign policy experts recommended that Trump should signal he would veto any sanctions that endanger the JCPOA and use the deal to reduce tensions and deepen ties with Iran on other issues. The recommendations were part of a report published by the National Iranian American Council.

Trump, during a debate with Democratic opponent Hillary Clinton this summer, called the agreement "one of the worst deals ever made by any country in history."

It's unclear whether Trump will try to make good on his promise to dismantle the deal or how his administration might tackle its implementation differently from President Obama's. Conservative lawmakers have questioned how aggressively the Obama administration is penalizing Iran for its destabilizing activities in the Middle East and how strictly it is enforcing the deal.

Cardin, who has voted with Republicans against the Iran nuclear deal, cautioned the Trump camp against unraveling it.

"You talk about unraveling the [Iran deal] to do what, to allow Iran to move forward on a nuclear weapons program," Cardin said. "What are you replacing it with, and do you have the support of the international community … that's something the Trump administration will have to weigh, and the support in Congress will depend on what they do."

Another Democrat on the Senate Foreign Relations Committee, Sen. Patrick Murphy, of Connecticut, said that now that the deal is in place, he has heard from Iran deal opponents who say that they want it left alone.

"There are a lot of people who opposed the deal who have watched its successful implementation who are worried about it unraveling," Murphy said.

"I think it's more than a little naive to think that the Europeans and the supreme leader [of Iran] are going to want to come back and re-negotiate the deal with president Trump."

Email:     jgould@defensenews.com   

Twitter:     @reporterjoe   

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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