The United States and its European allies are putting together a new offer for talks with Iran over its nuclear program, but would include tougher conditions than those rejected by Iran last year, The New York Times reported.
The newspaper cited a senior U.S. official as saying the Obama administration and its partners were "very close to having an agreement" on a position to present to Tehran.
Iran has welcomed the offer of talks, which the Western powers want to yield a deal curbing its enrichment drive and opening it to U.N. nuclear inspectors in exchange for a package of benefits. But Tehran has yet to formally reply to an invitation for talks in Vienna from Nov. 15 to 17.
The Times said the new offer would require Iran to send more than 4,400 pounds (2,000 kg) of low-enriched uranium out of the country. That would represent a more than two-thirds' increase from the amount required under a tentative deal a year ago.
The paper said the increase reflected Iran's steady production of uranium the past year and Washington's goal to ensure Iran has less than than a bomb's worth of uranium on hand.
Iran would also be required to stop all production of nuclear fuel it is enriching to 20 percent, a key step toward bomb-grade levels.
The Times said intelligence analysts concluded that last year's deal was scuttled by Iran's supreme leader, Ayatollah Ali Khamenei. Many officials therefore suspect this latest effort to fail, the Times said.
A Western diplomat in Vienna told Reuters: "Discussions are still under way. I wouldn't describe it as a new offer. I think primarily it is speculation. Of course, time has moved on since last year."
"Iran has taken up 20 percent enrichment which is not justified if there were to be a fuel swap ... so that would be a new element which would have to be contemplated."
Iran began loading fuel into the core of its first nuclear power plant on Tuesday, its atomic energy chief said, the last major step toward realizing its stated goal of becoming a peaceful user of nuclear energy.
Officials said the fueling at the Bushehr plant showed Iran's nuclear plans were on track despite sanctions aimed at forcing it to curb uranium enrichment that many countries fear is aimed at developing atomic bombs.
A U.N. Security Council resolution passed in June, imposing a fourth round of sanctions, renewed a call on Iran to suspend uranium enrichment, something Tehran has explicitly refused to do, saying such activity is its right under international law.