Iran said on Monday further talks with Russia to discuss a proposal to process fuel on Russian soil for Iran's nuclear stations would not be held this week as scheduled.
"Talks with Russia have not been cancelled but the date should be discussed," government spokesman Gholamhossein Elham told a weekly news conference.
The proposal has been put forward by Moscow to ease international concerns that Iran could produce bomb-grade material at home through enrichment.
But Elham said the proposal was only acceptable if it was in addition to enrichment facilities in Iran. "The government insists on enriching uranium and the proposal should be adjusted based on the new circumstances," Elham said.
Western countries have successfully pushed for Iran to be reported to the United Nations Security Council for failing to convince the world its atomic programme has an exclusively peaceful nature.
Iran says it only wants to produce low-grade enriched uranium for use in nuclear power rectors and that, as a signatory of the nuclear Non-Proliferation Treaty, it has a right to do so, reports the AP.
The Russian army is to test a new version of the Tupolev Tu-160M White Swan strategic missile carrier with the upgraded wing geometry