Republican Sen. Jeff Flake (Ariz.) will vote no on the Iran deal, according to Fox News. He was publicly undecided and one of the president's best hopes for getting bipartisan support for the deal, but on Saturday he announced that he will vote against the diplomatic agreement.

Currently, Congress is in recess. Flake issued a statement to announce his decision. "As written, this agreement gives Iran leverage it currently doesn't have," Flake said, Fox News reported.

His announcement makes it very likely that no Republicans in the Senate will back the Iran deal. Several Democrats have publicly announced that they will support the deal.

Flake is on the Senate Foreign Relations Committee. The White House has not commented on the statement, according to Politico. The Obama administration is expected to continue to look for Republican support regarding the deal.

"Hoping that Iran's nuclear ambitions might change after a 15-year sabbatical might be a bet worth making. Believing that Iran's regional behavior will change tomorrow - while giving up tools to deter or modify such behavior - is not," Flake said in his statement.

Obama must get support from at least 34 senators in order to sustain a presidential veto if Congress attempts to block the Iran deal, according to MSN. So far, 20 senators have announced that they support the deal. It requires that Iran reduce its nuclear capabilities. In return, the U.S. will lift economic sanctions on the country.