Israel was largely mum Wednesday on reports that Iranian negotiators had expressed support for a deal that - if accepted by their leaders - would delay Teheran's ability to make nuclear weapons by sending most of its known existing enriched uranium to Russia for processing.
International Atomic Energy Agency chief Mohamed ElBaradei said that representatives of Iran and its three interlocutors - the US, Russia and France - had accepted the draft for forwarding to their capitals. ElBaradei said he hoped for approval from all four countries by Friday.
Ali Asghar Soltanieh, Iran's chief delegate, praised the draft, saying it was "on the right track," while emphasizing that senior Iranian officials in Teheran still had to sign off on it.
"We have to thoroughly study this text and also (need) further elaboration in capitals," Soltanieh told reporters.
The apparent breakthrough came on the third day of talks in Vienna which aimed to overcome differences over Iran's nuclear intentions.
Both the Prime Minister's Office and the Foreign Ministry had no comment on the development, saying it was premature to discuss, since all that was being talked about at this time was a draft.
Government officials said it was too early to rejoice, because Iran had talked about sending enriched uranium to Russia for processing in the past, only to backtrack a short while later.
While the government's formal position was to refrain from commenting on the issue, Deputy Defense Minister Matan Vilna'i expressed satisfaction on Wednesday, telling Army Radio this showed "that the international pressure is working, but it must continue so that Teheran will not have a bomb."
ElBaradei said he had "circulated a draft agreement that in my judgment reflects a balanced approach to how to move forward."
"Everybody who participated at the meeting was trying to look at the future, not at the past, trying to heal the wounds," the IAEA chief added. "I very much hope that people see the big picture, see that this agreement could open the way for a complete normalization of relations between Iran and the international community."
Neither Soltanieh nor Elbaradei gave details of what was in the package. But diplomats told The Associated Press that it was essentially the original proposal drawn up by the IAEA that would commit Teheran to shipping 75 percent of its enriched uranium stockpile to Russia for further enrichment.
The official IRNA news agency in Iran quoted "informed sources in Vienna" as saying that Iran had not signed a deal.
"Iran has not signed any deal about meeting the fuel needs of the Teheran reactor," IRNA quoted the unidentified informed sources as saying.
It said reports that Iranian negotiators had expressed support for a draft deal on sending uranium for processing were "aimed at imposing psychological pressure on Iran... but Iran won't heed such pressure and will only decide on the basis of its national interests."
Sending such a large amount of Iran's enriched uranium outside the country would temporarily get rid of most of the material it needs to make a bomb.
After that material is turned into metal fuel rods, it would then be shipped back to Iran to power its small research reactor in Teheran, according to the draft.
Soltanieh suggested that his country - which held at least one one-on-one meeting with the American delegation - had wrested concessions from Washington in exchange for any agreement.
"One of the aspects in addition to the fuel is the control instrumentation and safety equipment of the reactor," the Iranian negotiator said. "We have been informed about the readiness of the United States in a technical project with the IAEA to cooperate in this respect."
He gave no details, and it was unclear whether the equipment he was describing fell under a UN embargo on shipping sensitive nuclear-related material to Iran, which is under Security Council sanctions for refusing to freeze enrichment.
While essentially technical, a deal that foresees Iran exporting most of its enriched material would have significant ramifications. It would commit Iran to turning over more than 1,200 kilograms of low-enriched uranium. That would significantly ease fears about Iran's nuclear program, since 1,000 kg. is the commonly accepted amount of low-enriched uranium needed to produce weapons-grade uranium.
French Foreign Minister Bernard Kouchner appeared to outline the contours of the deal, insisting that his country would not compromise on demanding that Teheran ship out most of its enriched material.
If Iran accepts the deal, "it must be before the end of the year, [and] there must be at least 1,200 kilograms - on that we won't back down," Kouchner told reporters in Paris.
Based on the present Iranian stockpile, the US has estimated that Teheran could produce a nuclear weapon between 2010 and 2015, an assessment that broadly matches those from Israel and other nations.
David Albright of the Washington-based Institute for Science and International Security, which has tracked Iran for signs of covert proliferation, said any deal would buy only a limited amount of time. He said Teheran could replace 1,200 kg. of low-enriched uranium "in little over a year."
In Washington, US Secretary of State Hillary Rodham Clinton did not specifically refer to the Vienna meeting or the potential deal, but said the US would engage with Iran if it was "serious about taking practical steps to address the international community's deep concerns about its nuclear program."
"The door is open to a better future for Iran, but the process of engagement cannot be open-ended. We are not prepared to talk just for the sake of talking," she said.