Secretary of State John Kerry is casting the choice on the Iran nuclear deal in stark terms - an agreement that would limit the Islamic nation's nuclear program, or no deal at all.
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Kerry is testifying before the Senate Foreign Relations Committee as the Obama administration publicly defends the much-debated accord. The administration is facing unified Republican opposition and doubts among some Democrats.
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Kerry also argues that if the deal is rejected, the diplomatic support the United States has garnered in recent years would evaporate.
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He tells the panel: "It's a question of how do you hold their program back."
Meanwhile, the Republican chairman of the Senate Foreign Relations Committee has told Secretary Kerry point-blank that "you've been fleeced" by the Iranians in the recently completed nuclear agreement.
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Kerry was greeted with applause from anti-war demonstrators as a handful of members from CodePink rose in the hearing room. But the mood turned critical immediately as Sen. Bob Corker, who heads the panel, gaveled the hearing to order.
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Corker told Kerry he was "fairly depressed" after listening to the secretary answer lawmakers' questions Wednesday about the agreement in a classified briefing.
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Kerry is testifying with Energy Secretary Ernest Moniz and Treasury Secretary Jack Lew about the deal Congress is expected to vote on in September. (AP)
