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The Banking Committee of the United States Senate on Thursday voted 18-4 in favor of advancing a bill that would toughen sanctions on Iran if international negotiators fail to reach an agreement on its nuclear program by the end of June, Reuters reported.

However, the bill is not expected to come up for a vote in the full Senate until at least March 24.

Ten Democrats, including bill co-author Senator Robert Menendez, announced earlier this week that they will hold off on new sanctions for two months to allow time to reach a diplomatic solution.

Republicans would need those votes to pass the bill, and even more votes to override a veto threatened by President Barack Obama, who has called the measure a threat to the continuing nuclear talks with Iran.

In the committee, only four Democrats voted against the bill, which was also sponsored by Republican Senator Mark Kirk. The other six joined the panel's 12-member Republican majority to pass it, noted Reuters.

"This legislation has been carefully calibrated to achieve our ultimate goal, which is to prevent Iran from achieving nuclear weapon capability," Menendez said.

The panel's top Democrat, Sherrod Brown, was one of the no votes. He called on lawmakers to wait until June to pass any more sanctions, reflecting a debate in Congress about how it should best seek to influence the talks on Iran's nuclear program.

"If negotiations fail, Congress and the president will join hands in applying greater pressure. And we will be in a far better position to ask the rest of the world to join us," he was quoted as having said.

Menendez and Kirk’s bill is a toned down version of a previous bill they authored and which had gained momentum in Congress, but Obama lobbied hard against it and threatened to veto it.

Last week, even after Obama used his State of the Union address to argue against new sanctions, Menendez pushed for sanctions again, saying the Islamic Republic has been stalling for time while continuing to develop its nuclear program.

Iran and the West are continuing to engage in talks aimed at turning a temporary deal reached in November 2013 into a permanent one. However, they have thus far failed to make substantial progress and have already twice postponed a deadline for a permanent deal.