WASHINGTON (AP) -- Under pressure from President Barack Obama, the Democratic-controlled Senate could delay a likely vote on a new round of tough sanctions on Iran.
With talks between Western powers and Tehran scheduled in Geneva next week, the president has spoken to Senate Majority Leader Harry Reid, D-Nev., and other senators pressing for a delay in any additional penalties while dispatching Vice President Joe Biden and Secretary of State John Kerry to Capitol Hill to make a similar argument.
"If we're serious about pursuing diplomacy, then there's no need for us to add new sanctions on top of the sanctions that are already very effective and that brought them to the table in the first place," Obama said at the White House on Thursday.
Several Republicans and Democrats have rebuffed Obama, insisting that sanctions forced Iran to negotiate and the United States should not back down now.
Four Republican senators -- New Hampshire's Kelly Ayotte, Florida's Marco Rubio, Texas' John Cornyn and Illinois' Mark Kirk -- wrote to Obama on Friday expressing serious concerns that the United States was considering sanctions relief for Iran "valued at up to $20 billion - and, in exchange, Iran would not be required to dismantle a single centrifuge, close a single facility or ship outside its borders a single kilogram of enriched uranium."
The four talked about working with other senators on increased penalties on Iran. Sen. Bob Casey, D-Pa., said in a statement Thursday, "At this time, I see no reason to let up the pressure," while 63 House Republicans and Democrats wrote to Senate leaders urging them to act quickly on sanctions.
Republican and Democratic aides said Friday that debate on the annual defense bill could be delayed until later next week, in part because of Senate action on a separate pharmaceutical bill. Senators are expected to press for a vote on Iran sanctions as part of the defense bill, but that vote could slip until December.
Sen. David Vitter, R-La., wanted a vote during consideration of the pharmaceutical legislation on his measure to make lawmakers disclose which of their aides are enrolling in the president's new health care law as part of an ongoing effort to discredit "Obamacare."
Time spent on that bill could give Reid time to delay the defense bill and a likely vote on tough, new penalties on Iran just as negotiators are sitting down in Switzerland.
In a statement, Vitter said Reid couldn't use his amendment as an excuse.
"I'll be filing and asking for a vote on my amendment to show Congress' hidden Obamacare exemptions, but I will absolutely not give Reid the ability to hide the Obama priority of blocking Iran sanctions," Vitter said Friday.
The House overwhelmingly approved the sanctions in July. The legislation blacklisted Iran's mining and construction sectors and committed the U.S. to the goal of eliminating all Iranian oil exports worldwide by 2015. The Senate Banking Committee pushed off its parallel bill this week so lawmakers are eyeing the Senate defense bill.
Earlier, Samantha Power, the U.S. ambassador to the United Nations, said the administration needs more time -- without new sanctions -- to pursue a deal with Iran.
"We have to test this regime," she said on "CBS This Morning." One key obstacle, she said, would be the "generations of suspicion" between Washington and Tehran.
Pressure has been building within both parties in Congress to toughen economic sanctions already in place. Iran repeatedly has denied it is trying to build nuclear weapons.
Asked about Israeli Prime Minister Benjamin Netanyahu's assertion last week that Iran is taking advantage of U.S. and international patience, Power said she doesn't believe that's the case. "The sign that this is not a good deal" for Iran is that Tehran hasn't yet accepted it, she said.
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