Iran agrees to swap fissile materials in 'landmark' deal

In what some reports have called a ''stunning breakthrough'', Iran today said that it had struck a deal with Brazil and Turkey for a nuclear fuel swap. Under the deal, Iran will ship more than a tonne of enriched uranium to Turkey as part of an exchange in which Tehran would be given nuclear fuel rods for a medical research reactor.

The deal is intended to defuse the crisis over Iran's nuclear aspirations at a time when a new wave of sanctions is being discussed in the UN Security Council and Israel is apparently contemplating military action. The details of the deal, mediated by Brazil, have yet to be finalised and would have to win the backing of other nuclear powers and the International Atomic Energy Agency (IAEA) before it is implemented.

The exchange would entail Iran shipping 1,200kg of low-enriched uranium (LEU) to Turkey in return for the fuel rods. It is based on an agreement Iran struck last year in Vienna with Russia, France, the US and the IAEA. Earlier this year Tehran withdrew from that agreement, suggesting instead that the exchange be carried out on Iranian soil and in smaller batches – terms that were unacceptable to the other parties as they would not reduce Iran's reserves of fissile material potentially useful in ultimately making a bomb.

But it is far from clear if that is enough to ease international concern over Tehran's atomic ambitions and avert new sanctions.

Western diplomats reacted cautiously to the news of the deal, pointing out that at the time of the Vienna agreement 1,200kg represented about three-quarters of Iran's LEU stockpile. Seven months on it is about half. Even if it is shipped out, Iran would soon be able to replenish stocks sufficiently to make a nuclear bomb.

Iran has always insisted it has no intention of making nuclear weapons.