By Kristina Peterson, Carol E. Lee and Jay Solomon

WASHINGTON -- The Senate unanimously approved legislation Thursday reauthorizing sanctions against Iran for the next decade, heightening tensions between the two countries less than two months before a new administration promising an even tougher approach takes office.

In a 99-0 vote, the Senate approved a bill that would extend sanctions against Iran's ballistic missile development and weapons programs not covered by last year's landmark nuclear agreement. The measures were set to expire at year's end. Iran's government has warned that passing of the sanctions bill would be viewed as a violation of the nuclear agreement and that they would respond.

The measure bill passed the House in mid-November and is now headed to the White House, where President Barack Obama is expected to sign it.

"I expect the president will sign the legislation when it reaches his desk, and the secretary of state will retain the authority to continue to waive all of the relevant nuclear-related sanctions authorized by the legislation," a senior administration official said.

The official also stressed the White House's view that the renewal of these sanctions "does not constrain the United States' ability to uphold our commitments" in the nuclear agreement and that as long as Iran "adheres to its commitments" in the agreement, "we will remain steadfast in our commitment to maintain sanctions relief."

Lawmakers said the legislation was needed to ensure that sanctions remain in place next year to keep Tehran in check, given that other international sanctions were loosened under the nuclear deal.

"This is even more important given how the current administration has been held hostage by Tehran's threats to withdraw from the nuclear agreement and how it has ignored Iran's overall efforts to upset the balance of power in the greater Middle East," Senate Majority Leader Mitch McConnell (R., Ky.) said on the Senate floor Thursday.

As the U.S. legislation advanced, Iranian officials said that the country may increase its stockpile of enriched uranium, a move that could spark a new international crisis in the weeks before Donald Trump takes office.

"Iran has made necessary preparations for potential U.S. decisions about the extension of sanctions," the head of Iran's Atomic Energy Organization, Ali Akbar Salehi, said Monday, according to Iranian state media.

Iranian foreign minister Javad Zarif and Secretary of State John Kerry both are attending meetings in Rome this week, although State Department spokesman Mark Toner said he wasn't sure if the two would meet.

U.S. lawmakers agreed with White House officials that the sanctions bill doesn't violate the nuclear deal with Iran and five other world powers. That July 2015 agreement imposed strict curbs for a decade on Iran's nuclear program in exchange for lifting tight international sanctions on Tehran, contingent on Iran's compliance with the deal.

Sen. Chris Coons (D., Del.) said he rejected Iranian claims that reauthorizing the sanctions violated the terms of the nuclear deal.

"These are not new sanctions. All we are doing is extending the expiration date of sanctions that are legal, already in place and a key part" of the nuclear deal, Mr. Coons told reporters Thursday. While it could lead to "aggressive posturing among hard-liners in Iran" in the run-up to their presidential election, "I don't expect Iran to walk away from the deal over this clean, 10-yearextension of existing sanctions law," he said.

Mr. Obama is trying to fortify the sanctions agreement before his term ends. Mr. Trump said on the campaign trail that he planned to renegotiate the accord.

Mr. Trump's first two picks for his national security team -- retired Army Gen. Mike Flynn as national security adviser and Rep. Mike Pompeo (R., Kan.) as Central Intelligence Agency director -- are hard-liners on Iran who have voiced opposition to the nuclear deal.

Some Republicans who were critical of the nuclear deal also are skeptical about undoing it now that international sanctions have been eased.

"It would be difficult to go in and repeal portions of the deal because the money has already flowed, sanctions have been relieved," said Sen. Jeff Flake (R., Ariz.). "We wouldn't want to relieve Iran of their obligations under the deal."

Senate Foreign Relations Committee Chairman Bob Corker (R., Tenn.), who is under consideration to be Mr. Trump's secretary of state, said that renegotiating the deal was a possibility.

"That's something that could well happen," Mr. Corker said Thursday, suggesting that Mr. Trump appoint one person in charge to "radically enforce" the deal while all possibilities are explored for its future.

Felicia Schwartz contributed to this article.

Write to Kristina Peterson at, Carol E. Lee at and Jay Solomon at

(END) Dow Jones Newswires

December 01, 2016 17:06 ET (22:06 GMT)

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