Iran has agreed to ship much of its enriched uranium to Turkey in a nuclear fuel swap deal reached with the help of mediation from Brazil and Turkey.
The agreement could revive a UN-backed proposal for easing the international stand-off over Iran's nuclear programme.
The official IRNA news agency quoted Iranian Foreign Ministry spokesman Ramin Mahmanparast as saying that a fuel swap will take place in Turkey.
The deal was reached during talks between Brazil's president, Luiz Inacio Lula da Silva, Turkish Prime Minister Recep Tayyip Erdogan and Iranian President Mahmoud Ahmadinejad in Tehran.
Iran has agreed to ship most of its enriched uranium to Turkey in a nuclear fuel swap deal that could ease the international stand-off over the country's disputed nuclear programme.
The deal was reached in talks with Brazil and Turkey, elevating a new group of mediators for the first time in the dispute over Iran's nuclear activities.
There was no immediate comment from the US and the other world powers which have led earlier negotiations as to whether the new deal would satisfy them and stave off a fourth round of UN sanctions.
It was agreed during the meeting of Iranian, Turkish and Brazilian leaders that Turkey will be the venue for swapping Iran's stocks of enriched uranium for nuclear fuel rods to power a medical research reactor, foreign ministry spokesman Ramin Mehmanparast said on state television today.
The deal would deprive Iran - at least temporarily - of the stocks of enriched uranium that it could process to the higher levels of enrichment needed in weapons production.
The material returned to Iran in the form of fuel rods could not be processed beyond its lower, safer levels, which are suitable for use in the Tehran research reactor.
The deal goes to the heart of international concern over Tehran's nuclear activities. Earlier negotiations led by Germany and the five permanent UN Security Council members - the US, Britain, France, Russia and China - have sought to stop Iran from enriching uranium, and thereby deprive it of a possible pathway to nuclear weapons.
The deal was announced after talks between Brazil's president, Luiz Inacio Lula da Silva, Turkish prime minister Recep Tayyip Erdogan and Iranian leader Mahmoud Ahmadinejad in Tehran.
The deal could revive a plan drafted by the UN and first proposed in October, though it's not clear exactly how close it is to the original proposal, which was ultimately rejected by Iran after some initial mixed signals.
Some of the details provided by Mr Mehmanparast, are the same.
For example, under the new plan Iran will ship 2,600lbs (1,200kg) of uranium enriched to low levels to Turkey to trade it for fuel rods containing uranium enriched to higher levels, he said.
That would happen one month after a final deal is signed between Iran and its main negotiating partners and the UN's nuclear watchdog, the International Atomic Energy Agency.
It appears Iran had dropped an earlier demand for the fuel exchange to happen in stages, rather than providing its material in a single batch. It has also dropped an insistence for the exchange to happen inside Iran.
Iranian Vice President Ali Akbar Salehi, who is also the head of the Atomic Energy Organisation of Iran, called today's deal historic.
Turkish Foreign Minister Ahmet Davutoglu said the deal meant "there is no longer any need for UN sanctions," Turkey's private NTV television quoted the minister as telling reporters in Iran.