New sanctions legislation from Congress could bring a halt to talks on limiting Iran's nuclear program, Iran's foreign ministry spokeswoman said Wednesday, as Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif met in Geneva to prepare for the next round.

“It is totally clear [that] using a worn-out tool which has been evidently proved ineffective is not helpful,” spokeswoman Marzieh Afkham said, according to Press TV.

Kerry and Zarif were to meet to pave the way for the next round of talks set to start Sunday between Iran and the "P5+1" group — the United States, Britain, France, Germany, Russia and China.

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It will be the second round of talks since a November 2013 interim deal was again extended on Nov. 24 for seven months. Negotiators hope to have the framework for a permanent deal in place by March and finalize it before the extension runs out June 30.

But a bipartisan group of lawmakers, concerned that the administration has lost the leverage necessary to reach a deal that would prevent Iran from being able to build a nuclear weapon, are preparing legislation to impose new sanctions on Tehran. Their efforts have been boosted by the administration’s seeming willingness to avoid offending Iran or accusing the country of actions that might jeopardize the talks.

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During a meeting with congressional leaders on Tuesday, President Obama repeated his opposition to new sanctions, noting that they could derail the talks, the White House said.

"Sanctions are one of, if not the biggest, reason we are at the negotiating table with Iran, because of the pressure we put on them, and that we have been able to move forward with diplomacy," State Department spokeswoman Marie Harf said Tuesday, but added: "It was through negotiations that we got to the Joint Plan of Action that we put in place that have halted the advance of its program."

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