"In light of the good relations and expanding cooperation between Tehran and Moscow, Iran expects Russia not to yield to the US biased approach and constant political pressure," Foreign Minister Kamal Kharazi was quoted as telling visiting Russian security chief Igor Ivanov.
Ivanov held a string of meetings here in Iran, which according to Iranian press reports were focused on the nuclear issue, the ongoing dispute over sharing Caspian Sea resources and the situation in the Caucasus.
Russia stands to earn 800 million dollars from building a nuclear power station at the southern Iranian city of Bushehr, but is facing a barrage of calls from Washington to abandon the lucrative deal.
The United States sees Iran's atomic energy programme as a cover for the development of nuclear weapons, but Moscow has so far refused to ditch the contract -- credited by some as having saved its struggling atomic industry.
Instead, Russia has been pressing Iran to continue cooperation with inspectors from the UN's International Atomic Energy Agency (IAEA), which last month criticised the Islamic republic for being less than forthcoming over its activities.
During his visit here, Ivanov also held two separate rounds of talks with Iranian national security chief and nuclear negotiator Hassan Rowhani, diplomatic source said, without giving any details.