The Zionist entity could find itself more isolated and more blamed by the international community if a nuclear deal with Iran is overturned by Congress, US Secretary of State John Kerry said Friday.

US Secretary of State John Kerry said Friday that the Zionist entity could find itself more isolated and more blamed by the international community if a nuclear deal with Iran is overturned by Congress.

"What happens is if the United States Congress unilaterally walks away from this agreement that we have reached, we go right back to square one where we were with no alternative, Iran is enriching, we have no inspections ... and we are going to have the conflict," Kerry said in a speech to the Council on Foreign Relations in New York.

Congress began Monday a 60-day review of the agreement reached July 14 between Iran and the U.N. Security Council's five permanent members - China, France, Russia, the U.K. and the U.S. - plus Germany.

The administration is seeking congressional support, particularly in the Senate, to ensure that lawmakers do not have a two-thirds majority in each congressional chamber to override a potential veto of legislation that undermines the accord.

With the deal, "we are gaining safety and security I believe for Israel and the region that no alternative presents", Kerry said, criticizing his opponents who voice concerns about what would happen after 15-20 years into the deal.

"The fact is that if we don't accept this agreement, if we don't keep to this agreement and put it to the test, year 15 or year 20 comes tomorrow, literally", he said. "Because Iran already has enough nuclear material for 10 to 12 bombs."

Kerry, however, said "Israel could actually wind up being more isolated and more blamed" if Congress rejected it.

"Nothing in this agreement is based on trust, nothing," he said.

The agreement reached in Vienna brought to a close nearly two years of contentious talks that focused on providing Tehran with sanctions relief in return for certain conditions on its nuclear program.