Weekend nuke talks with Iran run aground

that its nuclear intentions are peaceful. Among them was a revamped version of last year’s Tehran Research Reactor proposal, in which France and Russia agreed to provide Iran with much-needed fuel rods for a medical research reactor if Iran would part with a large chunk of its stockpile of enriched uranium. Such a deal would have left Iran with less than the minimum amount of nuclear fuel needed to make a single atomic bomb.

Iran, however, opened the talks on a jarring note, insisting it would not discuss any of the measures until Western powers agreed to end all economic sanctions and formally recognize Iran’s right to develop a wide range of nuclear technologies, including uranium enrichment. Iran has insisted that it has no plans to make atomic weapons.

After a frustrating start, the talks devolved into what one U.S. official described as “circular discussions” interrupted by lengthy breaks. At one point Friday, the Iranian delegation left the negotiations for Friday prayers followed by a lunch.

Afterward, chief Iranian negotiator Saeed Jalili stayed away for several more hours, complaining that he had a headache.

After the talks broke Saturday, Jalili spoke to reporters for nearly an hour, lashing out at Western powers for insisting on curbs for Iran’s nuclear program while sitting on large stockpiles of nuclear weapons. He stopped short of conceding that diplomacy had reached an impasse. “We are always open to dialogue,” he said.

The United States and the EU also held open the possibility of future talks but made clear that the next move is Iran’s. “The door remains open,” Ashton said. “The choice remains in Iran’s hands.”

Expectations for the Istanbul meeting had been low, but diplomats and some security analysts hailed the unanimity of the six world powers as a significant achievement and one that bodes well for the future.

George Perkovich, director of the nonproliferation program at the Carnegie Endowment for International Studies, a Washington, D.C. nonprofit group, said the talks had resulted in Iran “further isolating itself and losing support.”

It had hoped to turn eastward and demonstrate that China, India and others in the East would defend it against sanctions,” Perkovich said. “That effort failed, so Iran has nowhere else to turn.”

Iran’s increased isolation comes at a time when the country is suffering economically from the collective pressure of four rounds of UN sanctions.

Iran’s uranium enrichment program has also suffered significant setbacks, including a computer virus that damaged hundreds of centrifuges, U.S. officials have confirmed.

Clearly there are signs that Iran’s nuclear program has slowed,” said the senior Obama administration official, who spoke on the condition of anonymity to discuss details of the talks. “I think there is time and space for diplomacy.”