More than 1,000 American rabbis have signed an online petition asking members of the US Congress to oppose the Iran nuclear deal, which they say poses grave dangers to the United States and its allies including Israel.

Organised by Rabbi Kalman Topp, Senior Rabbi at Beth Jacob Congregation, Beverly Hills and Rabbi Yonah Bookstein, Co-Founder of Pico Shul, Los Angeles, the petition represents a "unified voice across religious denominations to express our concerns with the proposed nuclear agreement with Iran."

The US Jewish scholars and teachers urged lawmakers in both houses of the US Congress to vote in opposition to the deal.

Critics believe that the deal, which was intended to stop Iran from acquiring a nuclear weapon, will actually enable Iran to get such a weapon aside from getting back its $150 billion worth of frozen assets which it can use to finance terrorist movements worldwide, as it has done in the past.

"The Iranian regime denies basic human rights to its citizens, publicly calls for America's downfall and Israel's annihilation, and openly denies the Holocaust. This dangerous regime—the leading state sponsor of terrorism—could now be given the financial freedom to sow even more violence throughout the world" if the deal is approved by the US Congress, the rabbis' petition said.

Under the deal," the petition said, "Iran will not be subjected to "an airtight, comprehensive inspections structure—granting the regime the means to violate the agreement and develop a covert nuclear programme."

"The deal would also lift key arms embargos, so that in eight years Iran will be given international legitimacy to arm terror groups with conventional weapons and ballistic missiles," the petition warned.

"We fear the world we will leave our children if this deal is approved. And we fear having to someday bear the responsibility for Iran becoming wealthier, further empowered and better equipped to produce nuclear bombs when we had the chance to stop it," it added.

The petition said, "We hope and pray that God will assist us in ushering in for the entire world a time promised by Isaiah (2:4) when 'nation shall not lift up sword against nation, neither shall they engage in war anymore,' when peace will prevail. Until then, we simply cannot afford to empower and enrich a regime that continues to lift its sword without mercy towards so many who stand for good, freedom and peace."

President Barack Obama earlier said that under the deal, "Iran will not be able to acquire the enriched uranium that could be used for a bomb."

When the deal is implemented, he said, Iran will remove two-thirds of its centrifuges and for the next decade, the country will not enrich uranium and it will get rid of 98 percent of its stockpile of enriched uranium for the next 15 years.

"And, in fact, this deal shuts off the type of covert path Iran pursued in the past. There will be 24/7 monitoring of Iran's key nuclear facilities. For decades, inspectors will have access to Iran's entire nuclear supply chain — from the uranium mines and mills where they get raw materials, to the centrifuge production facilities where they make machines to enrich it," he said.

However, critics both in the US and overseas do not share Obama's optimism.