No peaceful alternative to Iran nuclear deal - Obama

US president Barack Obama argued that the debate over the landmark nuclear agreement with Iran is a choice between diplomacy and war, urging critics in Israel and Washington to aknowledge that their only viable alternative to the dealwould be military action.

Obama challenged critics of Tuesday's deal to present a better alternative - seen as a veiled reference to his Republican opponents in Congress.

“There really are only two alternatives here: either Iran getting a nuclear weapon is resolved diplomatically through negotiation,” Obama said. “Or it is resolved through force, through war. Those are the options.”

Under the deal, cemented between Iran and a coalition of world powers, international sanctions that have crippled Tehran’s economy will be gradually lifted once it shrinks and mothballs its nuclear infrastructure, accepting extensive surveillance at enrichment sites.

However, the agreement must first survive a longshot attempt by hawks in Washington to sabotage the accord with both the House of Representatives and the Senate branches of Congress in the US controlled by the opposition Republican Party. Earlier this year, lawmakers passed a resolution giving them authority to review the deal within the next 60 days.

Obama has been holding an intense public lobbying campaign to convince Congress to approve the deal. He has also threatened to veto any measure against the Iran deal.

He said that in the absence of a deal, the international economic sanctions that brought Iran to the negotiating table will unravel, and the world community will be unable to put the sanctions regime together.

"Without a deal, we risk even more war in the Middle East, and other countries in the Middle East would feel compelled to develop their own nuclear weapons," Obama said, adding that such a chain of events would risk a nuclear arms race "in the most dangerous region in the world."

Obama however ruled out the re-establishment of a formal diplomatic relationship with Iran similar to Cuba in the near future.    

Later, the White House published a readout of a phone call between Obama and Russian President Vladimir Putin, in which the US president thanked his counterpart for supporting the deal.

"The President thanked President Putin for Russia's important role in achieving this milestone, the culmination of nearly 20 months of intense negotiations," the statement said.