As Western governments awaited Iran´s response to a draft agreement with the major powers drawn up by the UN nuclear watchdog, Ahmadinejad broke with his usual hardline rhetoric to welcome the prospect of nuclear cooperation.
Iranian media said the government was likely to seek some changes to the proposals from the International Atomic Energy Agency and its envoy to the watchdog said he expected to be involved in further negotiations.
But Ahmadinejad insisted that his government, for so long on a collision course with the West over its refusal to heed repeated UN Security Council ultimatums to suspend uranium enrichment, was keen to strike a deal.
"We welcome fuel exchange, nuclear cooperation, building of power plants and reactors and we are ready to cooperate," the president said in a speech in Iran´s second city of Mashhad broadcast live on state television.
He said the West had previously talked of "halting and suspending everything, but now they are talking about fuel exchange, nuclear cooperation, building nuclear power plants and reactors. They have moved from confrontation to cooperation."
He said that as a result "the conditions for nuclear cooperation are ready".
"Now the IAEA is returning to its actual position which is to help independent nations and to create healthy relations with other nations," he said, referring to the UN watchdog which just completed an inspection visit to a second uranium enrichment plant Iran is building south of the capital.
Alluding to the three sets of UN sanctions imposed on Iran over its failure to suspend uranium enrichment, Ahmadinejad said the West had previously adopted a policy of "confrontation and threats, but today it has changed its attitude and we welcome it.
"We accept any hand extended to us in trust and honesty, without any plot or lie. But if that proves not to be the case, our response will be the same as we gave to (US president George W) Bush and his cronies," he said to cheers from the crowd.
Uranium enrichment is the sensitive process that lies at the heart of Western concerns over Iran´s nuclear programme. It can produce fuel for nuclear reactors or, in highly extended form, the fissile core of an atomic bomb.
Under the terms of the deal drawn up by the IAEA and already approved by Western governments, Iran would export to Russia more than 1,200 kilos (2,640 pounds) of its 3.5 percent low-enriched uranium (LEU) for refining up to 20 percent purity to fuel a Tehran reactor that makes medical isotopes.
France would then fashion the material into the fuel rods for the reactor.
Iran had originally been expected to respond to the proposals by last Friday but delayed its response amid conflicting views within the regime.
Iran´s hardline Javan (Young) paper said the government was set to seek changes to the pace at which it shipped out its LEU.
It would offer its stock "gradually" in several batches rather than sending out the full 75 percent of its supplies in one go as envisaged in the IAEA draft, the newspaper said quoting an unnamed informed source.
It would also seek to receive highly enriched uranium fuel at the same time as it hands over its LEU stock "as per a formula to be calculated by the IAEA based on the needs of the Tehran reactor."
Western governments want Iran to ship out as much of its LEU stock as possible as they fear it could enrich it further on its own and use it in making atomic weapons, an ambition Iranian officials strongly deny.
In Vienna, Iran´s envoy to the IAEA, Ali Asghar Soltanieh said he expected there to be further negotiations on what he insisted was a "technical" issue between Iran and the watchdog.
He said any deal also had to take into account the Islamic republic´s economic concerns.
"The Islamic Republic of Iran considers this merely (a) technical meeting between Iran and IAEA and we expect that our technical and economic concerns will be taken into consideration when dealing with the modalities of supply of nuclear fuel for Tehran research reactor," Soltanieh told reporters.
"As a representative of the Islamic Republic of Iran to these negotiations, I am entrusted to make every effort that these technical and economic concerns will be taken into consideration during negotiations and to be realised during negotiations in Vienna."
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