"Iran is not to give any of its 1200 kilograms fuel to the other party to receive 20 percent [enriched] fuel and whether gradually or at once, this will not be done and is called off," Alaeddin Boroujerdi told the ISNA news agency.
The Iranian official was referring to a recently drafted UN proposal according to Iran would transfer 1.2 tons of low-enriched uranium produced in its nuclear site Natanz to Russia, where it would be enriched to 20 percent, then to be transferred to France for industrial processing, after which it would be returned to the Tehran Research Reactor, which produces medical isotopes.
Boroujerdi also stated that Iran and fuel supplier countries must find a new way to provide Tehran's reactor fuel.
"Presently, Mr. Soltanieh is in talks to find an approach for the issue," Boroujerdi added, referring to Tehran's envoy to the International Atomic Energy Agency (IAEA), Ali Asghar Soltanieh.
"Referring tp remarks by some western officials that Iran must respond to the IAEA brokered deal regarding purchase of fuel in two days, Boroujerdi said, "The west cannot see a deadline and we are not committed to their remarks."
On Friday, a hardline Iranian cleric told worshippers that the The United Nations nuclear watchdog is legally obliged to provide Iran with nuclear fuel for its research reactor without setting any conditions.
Ahmad Khatami, a member of a powerful clerical body that can appoint or dismiss Iran's supreme leader, said in a sermon broadcast on state radio that Iran was prepared to produce fuel for its Tehran reactor if world powers insisted on the deal.
"The International Atomic Energy Agency is legally obliged to provide fuel ... if you want to play games with us then I can assure you that we will produce it by ourselves," Khatami told worshippers at Tehran University. "The Iranian nation is wise and will not be deceived by the nuclear deal."
"Why should we send our low enriched uranium abroad? ... who can guarantee that you will then provide us with the needed fuel?" said Khatami.
The United States, Britain, France, Germany, Russia and China have tried for years to persuade Iran to suspend uranium enrichment activities in return for economic and political incentives.
Tehran has so far refused to halt its enrichment.
Katami said Iran had no intention of yielding to the West's pressure over its nuclear program.
"No one has traded over the Iranian nation's legitimate nuclear right," said the cleric in the sermon, which was broadcast live.
The West's priority is to reduce Iran's LEU stockpile to prevent any danger that the Islamic Republic might turn it into the highly enriched uranium needed for a nuclear bomb.