A top adviser to Iranian Supreme Leader Ayatollah Ali Khamenei has met with Russian President Vladimir Putin.
Ali Akbar Velayati, who advises Khamenei on international affairs, also held talks with Russian Foreign Minister Sergei Lavrov and Russian Energy Minister Aleksandr Novak.
The Kremlin said the meetings in Moscow on January 28 focused on bilateral relations, as well as regional and international issues, although few other details were disclosed.
The meeting comes amid warmer ties between Tehran and Moscow.
Russia and Iran agreed to expand military cooperation during a visit by Russian Defense Minister Sergei Shoigu to Iran on January 20.
Shoigu said the agreement includes expanded cooperation against terrorism, exchanges of military personnel for training purposes, and an understanding enabling each country's navy to use the other's ports more frequently.
Iranian Defense Minister Hossein Dehqan said he and Shoigu had agreed on the need to foster cooperation to prevent "interference of external forces in regional affairs."