Kerry defends Iran nuclear deal, challenges skeptical critics in Congress

U.S. Secretary of State John Kerry on Thursday defended the recently negotiated nuclear deal with Iran, saying the accord is the only chance to curb Tehran's nuclear program.

"If the U.S., after laboriously negotiating this multilateral agreement with five other partners, were to walk away from those partners, we're on our own," Kerry told the Senate Foreign Relations Committee. "We will have squandered the best chance we have to solve this problem through peaceful means."

Iran and six world major countries -- the U.S., Britain, China, Russia, France and Germany -- reached an agreement on the Iranian nuclear issue that will put Iran on the path of sanctions relief but more strict limits on its nuclear program.

Many members of the U.S. Congress have expressed deep concern about the deal, warning that Tehran could evade inspections and use the money from sanction relief to destabilize the region. Congress is in the midst of 60-day review period of the deal.

Testifying before the panel with Energy Secretary Ernest Moniz and Treasury Secretary Jack Lew, Kerry said, "The alternative to the deal we've reached isn't ...a better deal, some sort of unicorn arrangement involving Iran's complete capitulation. That's a fantasy, plain and simple."

"The choice we face is between an agreement that will ensure Iran's nuclear program is limited, rigorously scrutinized, and wholly peaceful. Or no deal at all," the top U.S. diplomat told senators.

Republican Senator Bob Corker, chairman of the Senate Foreign Relations Committee, blasted Kerry and said the U.S. had been " fleeced" by Iran.

"I believe that you have crossed a new threshold in U.S. foreign policy -- where now it is a policy of the United States to enable a state sponsor of terror to obtain sophisticated, industrial nuclear development program that has, as we know, only one real practical need," Corker said.

"We know who we are dealing with. This is a state sponsor of terrorism," Democratic Senator Benjamin Cordin, ranking member of the panel, said of Iran. "Since there is no trust, the inspection and enforcement regime is particularly important."

Cordin said he hoped Obama Administration officials could provide answers that would provoke a debate in Congress and among American people, and "help us make the right decisions."

U.S. President Barack Obama had vowed to veto any congressional attempt to block the implementation of the Iran nuclear deal. It requires two-thirds approval in both the House and Senate to override the veto. Endite