Russian bombers used the Hamadan air base in Iran to carry out air strikes against the Islamic State in Syria on Tuesday.
Foreign Minister Sergey Lavrov said there was no motive to suggest Russia had violated resolution 2,231 of the United Nations Security Council.
Speaking at a press conference with New Zealand's visiting Foreign Minister Murray McCulley, Lavrov said there had been no supplying, sale or transfer of combat jets to Iran.
United States Secretary of State John Kerry expressed concern on Tuesday over the deployment of Russian aircraft in Iran, saying it could be in violation of the UN resolution.
Accusations levelled by Washington detracted from the main goal of establishing an end to the crisis in Syria, Lavrov said.
US State Department spokesman Mark Toner said on Tuesday that Moscow was carrying out the majority of its air strikes on the Syrian opposition forces, while telling everyone its targets are the Islamic State and Al-Nusra Front.
Russia on Tuesday recommenced its shelling campaign within Syria from the Hamadan air base in Iran, carrying out various strategic Tu-22M3 strikes.
