If Tehran follows the agreement, Obama said on Monday, it would chip away at years of mistrust with the United States.

"Huge challenges remain, but we cannot close the door on diplomacy, and we cannot rule out peaceful solutions to the world's problems. We cannot commit ourselves to an endless cycle of conflict," Obama said to critics of the deal.

Top Republicans - as well as US ally Israel - have criticized Obama for agreeing to the deal, which the United States and its partners claim will prevent Tehran from obtaining a nuclear bomb.

Obama has long been criticized for his desire to engage with US foes. As a presidential candidate in 2008, the former Illinois senator took heat for saying he would talk to Iran, which has not had diplomatic relations with Washington for decades.

The president seemed to want to make a victory lap with his remarks on Monday, which were mainly focused on immigration reform. He noted he had ended the war in Iraq and would end the war in Afghanistan next year, two things he also pledged to do as a candidate.

To his critics, Obama was especially direct.

"Tough talk and bluster may be the easy thing to do politically, but it is not the right thing for our security," he said.

The White House has declined to identify a date for the next round of talks between Iran and world powers Russia, China, the United States, France, Britain, and Germany. But a spokesman said on Monday that Washington was eager to get started quickly.

NTJ/BA