"I believe that frankly the ball is very much in the Iranian court," said Mohammed ElBaradei, the outgoing head of the International Atomic Energy Agency (IAEA). "I hope that they will not miss this unique and fleeting opportunity.... I hope that we will get an agreement by the end of the year."
Though the IAEA has not received a rejection in writing, officials in Tehran have issued a raft of sometimes contradictory statements that they do not like the original offer, which would ship out of Iran the bulk of the country's low-enriched uranium (LEU) in exchange for higher-enriched nuclear fuel it needs for a research reactor.
"It does look at this stage as though, if [the deal] is not dead, it's in the very last breaths of life," says Mark Fitzpatrick, a nuclear nonproliferation expert at the London-based International Institute of Strategic Studies (IISS).
"So far I haven't seen anything that Iran has suggested that is acceptable," says Mr. Fitzpatrick, contacted by telephone in Beijing. "For the US, for the West in general, the bottom line is that the bulk of Iranian LEU leaves Iranian soil, so it cannot be immediately put to weapons use."
Iran is already under three sets of UN Security Council sanctions that demand it halt its enrichment activities.
Iran hamstrung by internal divisions
Iran first tentatively agreed to the deal in Geneva on Oct. 1. But the government of President Mahmoud Ahmadinejad – who was declared reelected in a disputed vote this past June – came under fierce attack inside Iran from both fellow conservatives and opposition leaders for "giving away" the first fruit of Iran's nuclear program.
Iran's Islamic system of rule has been hamstrung by internal divisions and continued fallout from the aftermath of what officials admit was the most serious crisis faced by the Islamic Republic in the 30 years since the 1979 revolution.
Public statements on the all-important nuclear issue seem to bear that out. On Wednesday, Foreign Minister Manouchehr Mottaki appeared to reject the offer, though he was quoted only by a semi-official news agency.
"We will definitely not send our enriched uranium out of the country," Mr. Mottaki was quoted as saying. "That means a simultaneous fuel swap inside Iran could be possible."
Simultaneous fuel swap
Tehran vows that it is only interested in peaceful nuclear power, but many Western governments suspect a secret weapons effort. The deal as offered would deprive it of the raw material to make an atomic bomb, a process that would require enriching it from its current 3.5 percent to 90 percent.
Iran needs fuel enriched to 20 percent for a small reactor in Tehran that produces medical isotopes. Officials have suggested the main sticking point is mistrust of the Russians, French, and others, who might trick Iran by not providing the new fuel.
But the real problem – unstated by Iran, but on the minds of analysts and diplomats familiar with the deal – is the removal from Iran of an immediate possibility of a nuclear weapons capability.
"If [the Iranians] want the fuel for the Tehran Research Reactor, this is the way they can do it. If they want to prove that their LEU is for peaceful purposes, this is the way to prove it," says Fitzpatrick of IISS.
"Iran doesn't want to part with the LEU, because they want to keep it as a weapons option, but that goes against everything that they purport to say," he adds. "They insist that it is for peaceful uses, but they don't want to part with it because of its security value. It's a huge contradiction in their position."
The foreign minister, while apparently rejecting the deal on the table, left the door open for a compromise – a position bolstered by other statements from Tehran that indicate adjustments in timing or other logistical details could clear the way to some arrangement.
Under the current deal, Iran was to ship its own LEU to Russia, which would then enrich it further and send it on to France for "fabrication" into fuel. Mottaki appeared to be suggesting that Iran hand over some of its own fuel – but rather than waiting for that to be fabricated abroad and returned to Iran, Iran would immediately receive pre-fabricated fuel from another country. Iran has also suggested exchanging smaller amounts than the 1,200 kg (more than 2,640 pounds) first agreed.
Mottaki appeared to be suggesting that Iran would consider making a simultaneous exchange on Iranian soil of some of Iran's own LEU for pre-fabricated fuel from another country.
A different message
One week ago, the chief of staff of Iran's armed forces, Gen. Hassan Firouzabadi had a different message altogether.
"We won't suffer from an exchange of fuel," Agence France-Presse quoted the Mehr News Agency as saying. "On the contrary, in obtaining fuel enriched to 20 percent purity ... a million of our citizens will benefit from the medical treatment and ... we will prove at the same time the bona fides of our peaceful nuclear activities."
The volume, said Mr. Firouzabadi, was not an issue: "The quantity of [LEU] that will be shipped out in order to obtain fuel is not so large as to cause damage."