Iran appears to have resumed converting small amounts of its higher-grade enriched uranium into reactor fuel, diplomats said on Sunday.
If this process is expanded, it could buy time for negotiations between Washington and Tehran on its disputed nuclear program, the diplomats from the International Atomic Energy Agency (IAEA) in Vienna told Reuters.
The possibility of Iran converting enriched uranium into fuel, slowing a growth in stockpiles of material that could be used to make weapons, is one of the few ways in which the nuclear dispute could avoid hitting a crisis by the summer.
The diplomats said that Tehran could otherwise have amassed sufficient stock by June to hit a "red line" set by Israel after which it has indicated it could attack to prevent Iran acquiring enough fissile material for a nuclear weapon.
The IAEA diplomats said that Iran had apparently resumed converting into fuel small amounts of higher-grade enriched uranium, thereby reducing the amount potentially available for nuclear weapons, though they had few details and one told Reuters that "very, very little had been done" so far.
A fuller picture is unlikely until a new IAEA report on Iran's nuclear activity, due by late February. The question is crucial in determining the size of its stockpiles and how close these are to Israel's red line. "We will all be doing the mathematics soon," said one diplomat.
Iran recently informed the IAEA that it planned to speed up its uranium enrichment program, using faster and more advanced centrifuges.
A document sent by IAEA officials to news agencies said that Tehran planned to upgrade enrichment equipment at its Natanz plant.
Uranium enrichment is at the heart of the global standoff over Iran's nuclear program, which Israel and much of the West believes is a guise for developing a weapons capability. Iran has denied the allegations.
The IAEA and Iran have held several rounds of talks aimed at getting IAEA inspectors access to Parchin, a military base near Tehran where the agency suspects Iran could have carried out experiments with explosives capable of triggering a nuclear weapon.
In mid-December the IAEA failed to reach an agreement for a "structured approach" for Iran to address what it calls "overall, credible" evidence of nuclear weapons research having been carried out until 2003 -- and possibly since then.
Another round of talks last month ended once again with no results. Iranian television said at the time that the sides will meet again on February 12.