The Obama administration has sweetened its offer to Iran in ongoing nuclear negotiations, saying it might accept Tehran operating 4,000 centrifuges, up from the previous 1,300, according to a semiofficial Iranian news agency.
The Mehr news agency also said Monday that Iran and the six world powers seeking to negotiate a nuclear deal remained divided over how much uranium-enrichment capacity the Middle East nation should be allowed to maintain, and how to lift punitive sanctions from its economy.
With a deadline for negotiators a month away, the two sides still differ on how to deal with two nuclear sites that have stirred international concern, the Arak heavy-water nuclear reactor and the Fordow underground enrichment facility, according to Mehr.
Iran and the six world powers — France, Britain, the United States, Germany, Russia and China — are seeking a deal that would ease international sanctions on Iran's economy as long as it accepts limits designed to prevent it from gaining bomb-making capability.
Mehr's account quotes conservative Iranian lawmaker Javad Qoddoushi, a member of the parliament's foreign affairs committee, which was briefed last weekend by Abbas Araqchi, a deputy foreign minister and nuclear negotiator.
The article doesn't specify when the administration unveiled its latest offer on centrifuges, which are used to enrich uranium for peaceful purposes but also potentially for nuclear weapons. It may have come last Wednesday, when U.S. Secretary of State John F. Kerry met in Vienna with Iranian Foreign Minister Mohammad Javad Zarif and European Union foreign policy chief Catherine Ashton to try to end a five-month impasse in the talks.
Araqchi told the Iranian lawmakers that the United States "made concessions," the news agency said.
The White House and State Department declined to comment.
Mehr's account doesn't address other potentially important details of the U.S. offer, such as whether the administration would require Iran to dismantle other centrifuges and whether the 4,000 could include newer and more capable models. Iran currently has 9,400 operating centrifuges and another 10,000 that are installed but not in operation.
Some analysts have been predicting that the United States and the other five world powers could end up with an offer of a few thousand centrifuges, a number that may be small enough to avoid strong resistance from Congress or the Mideast allies worried about the nuclear threat.
Cliff Kupchan, an Iran specialist at the Eurasia Group risk-consulting firm, said the 4,000 figure "is sellable in Washington," because with such an inventory it would still take Iran many months to complete a "nuclear breakout" — a sprint to gather enough enriched uranium for one weapon.
Ray Takeyh, an Iran specialist at the Council on Foreign Relations, said the U.S. sweetener may encourage Iran to drag out negotiations to see what better offer it might receive after a few more months of talks.
The Iranian negotiator "may be sitting there thinking: 'If I wait till March, how many will I have?' " Takeyh said.
Iranian and Russian officials have recently floated the idea of extending talks beyond the Nov. 24 deadline. Some observers think the group will end up extending the talks because they have been unable to overcome their impasse on key issues but don't want the talks to collapse.
The disagreements over Arak and Fordow could be serious setbacks for the negotiations. Advocates for the deal-making say the apparent progress on these issues could be used to justify a further extension of the talks.
U.S. officials have provided few details of the negotiations to journalists or U.S. lawmakers; much of what has emerged publicly has come from foreign diplomats.
Last week, Russian Deputy Foreign Minister Sergei Ryabkov said that Arak remained a sticking point, along with the issues of enrichment and sanctions relief.
Mehr is an independent organization but is affiliated with Iran's Ministry of Culture and Islamic Guidance.
Times staff writer Richter reported from Washington and special correspondent Mostaghim from Tehran.