The Islamic Republic has been under international pressure since it resumed uranium enrichment in January 2006, which some countries fear is part of a covert nuclear weapons program.
Tehran, which insists its nuclear program is intended for electricity generation, failed to meet the UN-set deadline to halt enrichment, which expired last week, and now faces international sanctions.
"Everything must be done to prevent a war, and this is exactly what we are doing now. So far, neither Tehran nor Washington has responded effectively enough," Sergei Lavrov told a meeting with students at the Moscow State Institute of International Relations.
He said Russia's European partners, the International Atomic Energy Agency and the UN leadership support Moscow's ideas.
"But they can only work if there is a consensus, which has not been achieved yet," he said
Iran's foreign minister renewed calls earlier Tuesday for Muslim states and 'non-aligned' nations to become involved in long-running international talks on his country's nuclear program.
"We believe the participation of other parties, for example the [Organization of Islamic Conference] OIC head and the chief of the Non-Alignment Movement, in talks on the Iranian nuclear issue could make the process more constructive and comprehensive," Manouchehr Mottaki told a news conference.
Tehran is trying to secure backing for its line from more countries. Like Iran, some members of the organizations - including Venezuela, Cuba and some Muslim states - have been fiercely opposed to international policies pursued by Washington, which has pushed to punish a defiant Iran and has refused to rule out military strikes on the country.
The five permanent UN Security Council members - the U.S., Russia, France, China, Britain - plus Germany held a preliminary meeting in London Monday to discuss further steps on Iran, following the UN nuclear watchdog's report on the country's defiance of UN enrichment-related demands and its ongoing work to build more enrichment centrifuges last week.
The six world powers agreed to continue discussions later this week on a new, tougher Security Council resolution on Iran, which is already under limited UN sanctions, while also pledging a commitment to diplomacy.
Mottaki reiterated Iran's position that it advocated further talks without preliminary conditions.
He was quoted in the media earlier Tuesday as saying that the UN demand to suspend enrichment as a precondition for further talks was illegal and "based on an erroneous political strategy," and repeated that Tehran would not impose a moratorium on its activities.
But he said Iran was ready for talks on guarantees that its nuclear program was for purely civilian purposes and to strengthen the nuclear nonproliferation regime.
Mottaki also reiterated that Iran was willing to cooperate in the nuclear sector with other countries.
A senior British diplomat said on condition of anonymity Monday that the six international negotiators were discussing the suspension of $20-billion-worth European loans to Iran, an embargo on arms supplies to the Islamic Republic and a travel ban for the country's nuclear officials, among measures to force Tehran to curb its nuclear ambitions, Russian media reported.