GENTHOD, Switzerland -- Iran and six world powers ended a landmark meeting Thursday with an agreement to take a new stab at overcoming years of mistrust generated by Tehran's nuclear program and meet again this month for wide-ranging discussions on the two sides' concerns.
Adding to the optimism generated by the decision to hold follow-up talks was a rare bilateral meeting between the senior U.S. and Iranian delegates to the meeting. In addition, diplomats said Iran will open its newly disclosed nuclear plant to U.N. inspectors, probably within a few weeks.
In Washington, President Barack Obama called the talks "a constructive beginning" but said that Iran must match its promises of cooperation with deeds.
Now that Iran has agreed to open its newly disclosed enrichment facility, it "must grant unfettered access" to inspectors within two weeks, Obama said.
"Talk is no substitute for action," Obama said. "Our patience is not unlimited."
But he said that, if Iran follows through with concrete steps, "there is a path to a better relationship" with the United States and the international community.
U.S. Deputy State Department spokesman Robert Wood said Undersecretary of State William Burns used the meeting with chief Iranian delegate Saeed Jalili "to reiterate the international community's concerns about Iran's nuclear program.
"He addressed the need for Iran to take concrete and practical steps that are consistent with its international obligations and that will build international confidence in the exclusively peaceful nature of its program.
"While the focus of the discussion was on Iran's nuclear program, both sides had a frank exchange on other issues, including human rights," said Wood.
The encounter appeared to be concrete proof of Obama's commitment to engage Iran directly on nuclear and other issues -- a sharp break from the policy under the Bush administration.
More broadly, the meeting suggested that Obama was putting his concept of U.S. foreign policy into action, with its emphasis on negotiating even with the nations that are most hostile to the United States.
Confirming that the seven nations planned to meet again, senior EU envoy Javier Solana said Iran had pledged to open its newly revealed uranium enrichment plant to International Atomic Energy Agency inspection soon.
Iran's disclosure of the new plant had threatened to poison the atmosphere of the talks, with the West saying Tehran only revealed it because it feared it would found out. Uranium enrichment can make both nuclear fuel and the fissile core of nuclear warheads.
Solana said Iran had pledged to "cooperate fully and immediately with the IAEA," and said he expected Tehran to invite agency inspectors looking for signs of covert nuclear weapons activity to visit "in the next couple of weeks."
At the United Nations, the Iranian Foreign Minister confirmed the plant would be opened to inspectors.
"The letter from the IAEA to the Islamic Republic of Iran, in response to the information we have provided in this respect, and with regard to the new facilities that are under construction, indicate the fact that the agency has appreciated Iran's move and dialogue for arranging a visit by the IAEA official is under way," Manouchehr Mottaki said.
Mottaki suggested his country's talks with the U.S. and five other world powers could be expanded to the "summit" level.
He said Iran was willing to discuss a variety of security, economic and political issues, although he did not specifically refer to nuclear issues, which the six powers consider the most critical topic.
The five permanent members of the U.N. Security Council -- the U.S., Russia, China, Britain and France -- plus Germany hope to persuade Tehran to freeze the enrichment program.
Going into Thursday's talks, one of the top U.S. goals was to get the Iranians to commit to a second round of talks within a couple of weeks in order to keep the dialogue in a compact timeframe. The U.S. assumption was that if Iran was willing to engage seriously on the nuclear issue, a positive sign would be its agreement to have a second meeting shortly.
U.S. Secretary of State Hillary Rodham Clinton, speaking in Washington shortly after the talks ended, called the day productive but sounded a pragmatic note, as well.
"I will count it as a positive sign when it moves from gestures and engagements to actions and results," she said. "That's a necessary pathway and I think we're on it. We've always said we would engage. But we're not talking for the sake of talking," she said, adding, "Today's meeting opened the door, but let's see what happens."