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Iran, 6 powers try to break deadlock in nuclear talks

MOSCOW - Negotiators from Iran and six world powers scrambled to preserve forward momentum for talks on Iran’s disputed nuclear program Tuesday, tentatively agreeing to hold another round of meetings - the fourth since April - despite little visible progress toward a compromise that would stop the drift toward war.

The talks Tuesday, the second day of the negotiations, had a stop-and-go quality to them and were extended repeatedly, evidently so that the sides could negotiate over the status of the next round of talks, which is expected to be held in China or Kazakhstan. It was unclear whether the negotiators, ensconced in a Moscow hotel across from the foreign ministry, would keep talking into Wednesday.

Russian officials, as the conference’s hosts, met twice with the head of the Iranian delegation Tuesday, in an evident attempt to keep the process from derailing.

The outcome of Monday’s talks made clear that the room for agreement is vanishingly small. Iran has concentrated its efforts on a weighty concession it seeks from the world powers: an acknowledgment that it has the right under international treaties to enrich uranium. In exchange, Iran - which has repeatedly asserted its nuclear program is peaceful - has signaled it may be willing to stop enriching uranium to 20 percent purity, considered a technical step short of bomb grade.

The six powers, known as the P5-plus-1 because they include the five permanent members of the UN Security Council - Russia, China, the United States, Britain, and France - plus Germany, have demanded that Iran abide by prior Security Council resolutions to suspend all uranium enrichment. They also have demanded that the Iranians ship the 20 percent-enriched uranium out of the country and shut down an underground enrichment facility.

Israel, which considers Iran its most dangerous enemy, has warned that it may preemptively strike suspected Iranian nuclear targets if it decides that the talks are not making progress, an action many fear would lead to a new Middle East war.

Rajab S. Safarov, director of Moscow’s Center on Iran Studies, said negotiators were under additional pressure to avoid a breakdown of the process after the publication of a joint statement Monday by President Obama and President Vladimir Putin, which urged the importance of finding a diplomatic solution. The two superpowers are united in their desire to avoid a war, he said.

The head of the influential National Security and Foreign Policy Committee of Iran’s parliament, Alaeddin Boroujerdi, told Iran’s semiofficial Mehr news agency Tuesday that recognition of the right to enrich is “a red line’’ for Tehran and the country will not “forgo’’ its legal right.

An Iranian diplomat attached to the delegation said Tuesday that the talks’ outcome depended on how the world powers respond to Tehran’s demands.