But many lawmakers seem to be having second thoughts about their vows to immediately hit Iran with new economic penalties if Tehran's negotiators didn't agree to curb the nation's controversial
Though many longtime lawmakers are eager for immediate penalties, it appears they don't have enough votes to override a threatened veto by President
"I don't think anybody in Congress wants to feel, quote, responsible for this deal falling apart," Corker told Bloomberg News' Al Hunt on the "Charlie Rose" television program. In crafting sanctions legislation, he said, "you realize that you're, in essence, to use a term, firing with real bullets."
Iran and the six powers — Britain, China, France, Germany, Russia and the U.S. — have been seeking a deal that would ease sanctions on Iran if it agrees to restrictions aimed at preventing it from gaining nuclear weapons capability.
It had been widely expected that if the negotiations failed to yield a deal by the deadline, Congress would step in with new sanctions on the theory that the penalties could force the Islamic Republic to give ground.
But private experts, as well as administration officials, have been arguing that such a step could drive Iran away from the negotiating table, or convince many nations that the United States, not the mullahs, is to blame if the talks fail. That could undermine the current sanctions by encouraging oil purchasing nations to increase purchases of Iranian petroleum.
Iran and the six world powers agreed last week to set a new deadline of March 24 to negotiate the broad outlines of a deal. The final details of the deal are to be completed by the end of June.
At a Senate Foreign Relations Committee hearing Wednesday, two experts who have supported tough sanctions urged committee members to hold off on new penalties.
Gary Samore, a former top White House nuclear advisor, told the committee the challenge was to devise legislation that would pressure Tehran "without giving the Iranians an excuse to renege on the joint plan of action and blame it on the United States, which would jeopardize our ability to go back to a sanctions campaign."
Discussion in the committee is now about "prospective sanctions should the deal not come together," a Senate aide said. Those penalties would be "down the road," to be "phased in over a period of time — calibrated and measured."
Elizabeth Rosenberg, a former Treasury Department sanctions expert now with the Center for a New American Security, said that "the lawmakers who want sanctions still want more sanctions. But they aren't a large enough majority to pass legislation that could override a veto."