Israel anticipates that the US Congress will heed its call and vote down the Iran nuclear deal against the wishes of the Obama administration, the head of the powerful Knesset Foreign Affairs and Defense Committee told Israel Radio on Tuesday."I'm convinced that the American Congress will reject by a large majority the nuclear agreement with Iran," MK Tzachi Hanegbi (Likud) said. "There is a plethora of explanations and reasons as to why the agreement weakens the United States."Hanegbi told Israel Radio that the government in Jerusalem was urging members of Congress to view the agreement through the prism of "what was good for their country, not Israel."The Israeli government certainly has its work cut out for it, especially after Senator Brian Schatz said on Monday he backs the US-led international nuclear deal with Iran, becoming the 16th senator to do so and moving President Barack Obama one vote closer to locking in enough Senate votes to make the deal fly.A liberal, Jewish-born lawmaker from Hawaii, Schatz had been expected to come down in favor of the deal. But his decision was noteworthy because it came just a few days after another Jewish senator, Democrat Chuck Schumer of New York, announced his opposition to the Iran agreement.Schumer's decision last week caused an uproar as he usually lines up behind the president. He is the No. 3 senator and wants to become Senate Democratic leader after the 2016 election.In a statement, Schatz said he was backing the pact between six world powers and Iran because it is the best option for keeping nuclear bombs out of Tehran's hands."Iran must never be allowed to have a nuclear weapon, and that is why I support this agreement," Schatz said.Prime Minister Benjamin Netanyahu opposes the agreement, as do some Jewish groups in the United States.Most Republicans have also said they oppose the deal, which was unveiled on July 14. It is designed to curb Tehran's nuclear program in exchange for lifting of economic sanctions.Republicans plan to push for a congressional "resolution of disapproval" that could cripple the deal. Obama is pinning his hopes on Democrats, in the minority in both houses of Congress.Several key votes on the deal are likely in weeks ahead after Congress returns from its August recess.Schatz said no military option could do what the agreement would do - deny Iran a bomb for at least 15 years."This agreement should not be compared to an imaginary deal where Iran rolled over and eliminated all its centrifuges and all peaceful nuclear energy generation. That was never seriously on the table," he said.Congress has until Sept. 17 to vote on any resolution of disapproval of the agreement. After Schumer's announcement last week, Democrats said they were still confident they could rebuff Republican attempts to sink the agreement.Reuters contributed to this report.