Russia has dropped plans to supply Iran with S-300 air defense missiles.
The chief of Russia's armed forces, General Nikolai Makarov, said the delivery of the missiles would violate U.N. sanctions.
The S-300 is a mobile, long-range air defense system that can detect, track and destroy ballistic missiles, cruise missiles and low-flying aircraft.
Western nations have opposed the sale, saying it would give Iran the means to withstand air strikes against its nuclear sites.
The U.N. imposed a fourth set of sanctions on Iran in June for refusing to stop enriching uranium.
Some information for this report was provided by AFP and Reuters.