Speaking to reporters at a regional security conference in Bahrain, Manochehr Mottaki said Iran agreed with a U.N. deal proposed in October in which up to 2,600 pounds (1,200 kilograms) of its uranium would be exchanged for fuel rods to power its research reactor.
"We accepted the proposal in principle," he said through a translator. "We suggested in the first phase we give you 400 kilograms of 3.5 percent enriched uranium and you give us the equivalent in 20 percent uranium."
Iran has about 3,300 pounds (1,500 kilograms) of low-enriched uranium and needs to refine to 20 percent to operate a research reactor that produces medical isotopes.
Uranium enriched at low levels can be used as fuel for nuclear energy, but when enriched to 90 percent and above, it can be used as material for a weapon. The United States and five other world powers have been trying to win Iran's acceptance of a deal under which Tehran would ship most of its low-enriched uranium stockpile abroad to be processed into fuel rods, which can't be enriched further.
The deal would leave Iran - at least temporarily - without enough enriched uranium to produce a bomb. However, after signaling in October that it would accept the proposal, Iran has since balked, giving mixed signals over the deal, including several statements from lawmakers rejecting it outright.
Mottaki maintained, however, that a clear proposal had been given involving the simultaneous exchange of uranium for fuel rods in stages.
"We gave a clear answer and we responded and our answer was we accepted in principle but there were differences in the mechanism," he said, suggesting the exchange take place on Iran's Kish island, in the Persian Gulf.
It is not clear, however, if the low-enriched uranium would then remain on the island or could be shipped out of the country
- a necessary condition to any deal from the standpoint of the international community.
The world powers are also unlikely to accept a long drawn out exchange in stages, as it would allow Iran to maintain enough enriched uranium inside the country to possibly build a weapon.