Russian and Iranian nuclear negotiators began a second day of talks today amid scepticism that they could ease international concerns that Tehran wants a nuclear bomb.
The two sides are discussing a Russian offer to enrich uranium for Iranian power plants on its own soil - seen by some as the last chance to defuse the row over Tehran's nuclear ambitions before Western governments seek UN sanctions.
Day one of the talks yesterday ended with no word on their outcome and only an agreement to reconvene the next day.
Interfax news agency said today's talks were talking place in the foreign ministry building - a shift of venue from yesterday's meeting in the Kremlin.
Iranian Foreign Minister Manouchehr Mottaki had already dampened expectations when he said in Brussels his country would press ahead with its nuclear work even if it accepted the Russian proposal.
The United States and the EU trio of Britain, France and Germany - the countries pressing Iran hardest on its nuclear plans - are looking ahead to March 6th when the UN nuclear watchdog is to report on Iran to the UN Security Council.
Washington wants sanctions against Iran, though veto-wielding members of the Security Council like Russia and China are cool on the idea.
Many Russian commentators were convinced Iran's decision to take part in the talks was an exercise to buy time.
The thinking behind Moscow's proposal is that if Russia processed uranium for Iran it could ensure the fuel was enriched only to the level suitable for power stations, and not to the higher grade needed for a nuclear bomb.