Russian President Vladimir Putin on Tuesday invited Iranian President Mahmoud Ahmadinejad to Moscow for talks, the Russian news agency Interfax reported.
The invitation followed a meeting between Putin and Ahmadinejad, who is fighting calls from Western powers to stop nuclear work that Washington says is aimed at building atomic bombs. Tehran says its intentions are peaceful.
"Ahmadinejad accepted the invitation with gratitude. The parties agreed to clear the dates for the visit through diplomatic channels," Interfax quoted the two leaders as saying in a joint statement.
Putin also agreed to bring Iran's Bushehr nuclear power plant into operation on schedule following talks in Tehran.
"The Bushehr nuclear power plant will be constructed and brought into operation in line with the agreed upon schedule," the statement said.
"The parties... reaffirmed that it will continue to be pursued strictly in line with their commitments under the treaty on the non-proliferation of nuclear weapons."
Russia's work on the plant has been drawn into the international row over Iran's nuclear ambitions. The United States, which along with some other Western powers sees the plant as part of a nuclear drive through which Iran may try to produce weapons, has urged Moscow to halt construction.
Russian contractors have repeatedly set back the completion date for the power station on the Gulf, provoking tensions between Moscow and Tehran.
Moscow has blamed financial problems for the delays. But many observers had previously said Russia is stalling because it does not fully trust Ahmadinejad and fears an international backlash if it delivers nuclear fuel to Bushehr.
Tehran says it only wants nuclear technology to generate power.
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