Responding to his critics, President Barack Obama forcefully defended the weekend nuclear agreement with Iran, declaring that the United States "cannot close the door on diplomacy."
The president's remarks came as criticism of the deal to temporarily freeze pieces of Iran's nuclear program mounted from Capitol Hill and some allies abroad, most notably Israel.
Obama acknowledged that tough obstacles remain before the diplomacy with Iran can be deemed a success, but he insisted the potential rewards are too great to not test Tehran's willingness to strike a longer-term deal with the US and other world powers.
"If Iran seizes this opportunity and chooses to join the global community, then we can begin to chip away at the mistrust that's existed for many, many years between our two nations," Obama said during an event in San Francisco.
For Obama, the shift to foreign policy could be a welcome change from the domestic problems that have plagued the White House in recent weeks, especially the troubled rollout of his signature health care law.
The president used the opportunity to remind Americans that the current diplomacy with Iran is in part the result of the pledge he made at his inauguration to talk to the Islamic republic without preconditions.
"When I first ran for president, I said it was time for a new era of American leadership in the world, one that turned the page on a decade of war and began a new era of engagement with the world," he said. "As president and as commander in chief, I've done what I've said."
The weekend agreement between Iran and the so-called P5+1 countries the United States, Britain, France, Russia, China and Germany is to temporarily halt parts of Tehran's disputed nuclear program and allow for more intrusive international monitoring of its facilities. In exchange, Iran gets some modest sanctions relief and a promise from Obama that no new economic penalties will be levied during the terms of the six-month deal.
The groundwork for the accord was laid during four clandestine meetings between US and Iranian officials throughout the summer and fall. An earlier meeting took place in March, before Iranians elected their new, more moderate-sounding President Hassan Rouhani. Details of the secret talks were confirmed to The Associated Press by three senior administration officials.
With a short-term pact in place, the US and its partners will now set about trying to negotiate a broader agreement with Iran to permanently neutralize the nuclear program and assuage international concerns. The US and its allies contend Iran is seeking a bomb, while Tehran insists it is pursuing a peaceful nuclear program for energy and medical purposes.