The federal agency overseeing Russia's military exports on Friday denied reports that the country is planning to deliver a powerful new anti-aircraft missile system to Iran.

Iran's defense minister had said earlier this week that Russia was preparing to equip Iran with the S-300 missile system, which would dramatically increase the country's ability to repel an attack.

But Russia's Federal Military-Technical Cooperation Service denied the claim in a brief statement.

"The question of deliveries of S-300 systems to Iran, which has now arisen in the mass media, is not currently taking place, is not being considered and is not being discussed at this time with the Iranian side," said the agency, known by its Russian initials, FSVTS.

The system is capable of shooting down aircraft, cruise missiles and ballistic missile warheads at ranges of over 90 miles and at altitudes of about 90,000 feet. Russian military officials boast that its capabilities outstrip the U.S. Patriot missile system.

The S-300 is an improvement over the Tor-M1 air defense missile system. Russia delivered 29 Tor-M1s to Iran this year under a $700 million contract signed in December 2005. Iranian media reports have claimed the improved missile systems could inflict significant damage on U.S. or Israeli forces, were they to attack Iran.

The United States had said in the past that it would not rule out military action as a way to halt Iran's nuclear enrichment, claiming it was using the nuclear program as cover for weapons development. But earlier this month, Washington reversed course, concluding in an intelligence assessment that Iran stopped direct work on creating nuclear arms in 2003 and that the program remained frozen through at least the middle of this year.

Russia has provided Iran with submarines and military planes in recent decades.