"We regret that Iran — as far as we can see — does not consider it possible to agree to the formula that it was offered," Lavrov told a news conference.
Under the plan, Iran would hand over most of its stocks of low-enriched uranium in return for the supply by France and Russia of nuclear fuel enriched to the higher level required for a Tehran research reactor.
Russia, a veto-wielding permanent UN Security Council member, is one of the few major powers to have close relations with Iran.
"Our aim is clear. We want that the international community does not have any doubt on the peaceful nature of the Iranian nuclear programme," added Lavrov.
He noted that the UN Security Council had the capacity to "study further measures on Iran" but once again did not come out explicitly in support of further UN sanctions against the country.
"Acting with a logic of punishing Iran… is not a sober approach," he said.
Western diplomats said this week that Iran had effectively rejected a proposal put forward by six major powers in talks in Vienna brokered by the International Atomic Energy Agency, the UN's nuclear watchdog.
However Iranian Foreign Minister Manouchehr Mottaki insisted Iran did not reject "the principle" of the nuclear fuel deal.
Amid increasing international frustration with Tehran, US Secretary of State Hillary Clinton vowed Thursday that the United States "will not be waited out" and "not back down" in the face of Iran's defiance.
Moscow's capacity to provide technical help for the Iranian nuclear drive is seen by some analysts as giving it an unmatched power of leverage in Tehran.
Russia is building Iran's first nuclear power plant in the southern city of Bushehr and the facility is due to finally come on line this year.
The West suspects Tehran is trying to develop a nuclear weapon under cover of its civilian nuclear energy programme. Russia has said there is no evidence to support these accusations.
