A Russian delegation headed by acting Security Council Secretary Valentin Sobolev arrived in Tehran on Sunday and is meeting with Iranian government officials, including the secretary of the Supreme National Security Council, Saeed Jalili.
The meeting comes as a follow up to Jalili's visit to Moscow in December 2007.
"Our talks are of a peaceful nature and are not directed against any third countries," Sobolev said.
He said the talks were proceeding "in the spirit of mutual understanding and mutual respect," adding that he hoped the meeting would help "advance Iranian-Russian relations."
Jalili said Iran would soon present "an array of proposals" designed to deal with global problems, adding that they included comprehensive initiatives concerning, in particular, political and security issues.
He took pains to stress that the proposals to be put forward for discussion included measures to promote nuclear nonproliferation.
Iran's Security Council said earlier the officials would discuss bilateral cooperation in security, including Iran's nuclear program, as well as topical international and regional issues, in particular the situation in the Middle East.
A delegation from the International Atomic Energy Agency, led by its deputy director general, Olli Heinonen, is to arrive in Tehran later on Monday to continue talks started last week on the Islamic Republic's nuclear program.
President Mahmoud Ahmadinejad said last week that Iran was prepared to try and reach an agreement with any country over its nuclear program, but would not bow to pressure to halt its development of peaceful atomic energy.
The international community has demanded that Tehran halt uranium enrichment, used both in electricity generation and nuclear weapons production. Iran insists on its right to civilian nuclear energy, and has defied three sets of relatively mild United Nations sanctions over its nuclear program.
Iran also announced this month it was installing another 6,000 uranium enrichment centrifuges at its underground facility in Natanz. This is in addition to the current 3,000. The country also announced tests of advanced enrichment centrifuges, along with plans to build a second uranium processing plant by next March.
The country's nuclear ambitions have fueled tensions with Washington, with U.S. President George Bush refusing late last year to rule out military action against Tehran.
Russia and China, which both have strong business interests in Iran, have blocked stronger sanctions against the country using their vetoes at the UN Security Council.
