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Sen. Chuck Schumer to oppose President Obama's Iran nuclear deal

The move is a blow to the Obama administration, which has lobbied hard for the international accord ahead of a vote next month.

New York's Chuck Schumer, the No. 3 Senate Democrat and the most influential Jewish lawmaker in Congress, says in an extensive statement posted online that he will oppose the Iran nuclear deal.

“I will vote to disapprove the agreement, not because I believe war is a viable or desirable option, nor to challenge the path of diplomacy,” Schumer wrote in his statement Thursday, “It is because I believe Iran will not change, and under this agreement it will be able to achieve its dual goals of eliminating sanctions while ultimately retaining its nuclear and non-nuclear power.”

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While Schumer’s announcement is a blow to President Obama, it comes after a flurry of key Senate Democrats announced they would vote in support of the deal, including Schumer’s New York colleague, Sen. Kirsten Gillibrand. Other Democrats who voiced their support of the deal were Sens. Bill Nelson of Florida, Tim Kaine of Virginia, and Barbara Boxer of California.

“Bottom line: Iran possessing a nuclear weapon would be a game-changing event that cannot and will not be allowed,” Gillibrand wrote in a statement Thursday, “That was true then — and it remains true today.”

Senate Republican leadership says they will vote on a resolution of disapproval related to the Iran nuclear deal when Congress returns in September from their month-long August recess.  

Under the Iran Nuclear Agreement Review Act signed into law in May, Congress has the chance to prevent the president from waiving or suspending the congressional sanctions if they have a 67-vote-strong veto-proof majority who opposes the deal. They must vote on a resolution of disapproval by September 17th.

The Obama administration has flooded Congress with classified briefings and public hearing appearances in an effort to answer questions of skeptical lawmakers.  Many Congressional Democrats have also been invited to the White House to discuss the deal with members of the administration.

Schumer, who is expected to be the next leader of the Senate Democratic Caucus after Democratic Sen. Harry Reid of Nevada retires at the end of this term, said on Wednesday that he was still undecided on the deal.

“This is one of the most important decisions a senator or congressmember can make, “ Schumer told reporters, “And I am getting a lot of questions answered, questions about what happens if we have an agreement, this agreement, what happens if we don't have this agreement.”

Obama chastised opponents to the deal during a scathing speech at American University Wednesday, saying “It's those hardliners chanting 'death to America' who have been most opposed to the deal. They're making common cause with the Republican caucus.”

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“Let’s not mince words: The choice we face is ultimately between diplomacy and some form of war — maybe not tomorrow, maybe not three months from now, but soon,” President Obama said during his speech, “How can we in good conscience justify war before we’ve tested a diplomatic agreement that achieves our objectives?”

McConnell hit back Thursday during a press conference, saying the president’s rhetoric was hurting more than helping.

“What is not helpful is rhetoric like the president has been using as recently as this morning, comparing Republicans in Congress who have legitimate concerns over the Iran nuclear agreement to those in the streets in Teheran yelling 'Death to America,'" McConnell said.

“My view of this issue is rather than this kind of -- kind of crass political rhetoric, we ought to treat this issue with the dignity that it deserves,” McConnell said.