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Iranian negotiators on Wednesday expressed support for a deal that — if accepted by their leaders — would delay Tehran's ability to make nuclear weapons by sending most of its existing enriched uranium to Russia for processing, diplomats said.

International Atomic Energy Agency chief Mohamed ElBaradei said that representatives of Iran and its three interlocutors — the U.S., 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 Tehran 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. While the United States and other nations fear Iran may be interested in developing nuclear weapons, Tehran insists its activities are peaceful and meant only to generate energy for its growing population.

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."

Secretary of State Hillary Clinton says the U.S. will not talk to Iran merely for the sake of talking, according to a Reuters report. Clinton says Iran must take immediate measures to execute steps on low enriched uranium.

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 Tehran to shipping 75 percent of its enriched uranium stockpile to Russia for further enrichment.

After that material is turned into metal fuel rods, it would then be shipped back to Iran to power its small research reactor in Tehran, according to the draft.

The diplomats spoke on condition of anonymity because the meeting was confidential.

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 if the equipment he was describing fell under a U.N. 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 political and strategic ramifications.

It would commit Iran to turn over more than 2,600 pounds of low-enriched uranium. That would significantly ease fears about Iran's nuclear program, since 2,205 pounds 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 Tehran ship out most of its enriched material.

If Iran accepts the deal "it must be before the end of the year, 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 U.S. has estimated that Tehran 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 Tehran could replace 2,600 pounds of low-enriched uranium "in little over a year."

The Associated Press and Reuters contributed to this report.