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While the diplomatic discussions about Iran continue, along with the sanctions on nuclear technology, Russia has gone ahead with the sale of new conventional weapons.

Moscow has sold Iran anti-aircraft missiles, as NPR's Gregory Feifer reports from the Russian capital.

GREGORY FEIFER: Defense Minister Sergei Ivanov announced the fulfillment of Moscow's billion dollar deal with Iran to reporters on Tuesday.

Mr. SERGEI IVANOV (Defense Minister, Russia): (Speaking foreign language)

FEIFER: We have supplied a modern short-ranged Tor-M1 anti-aircraft missile systems in accordance with our contract, he said. Iran is not under international sanctions.

The deal has angered Washington, which accuses Iran of being the world's leading state sponsor of terrorism. Tehran is suspected of developing a secret nuclear arms program and is under U.N. sanctions against atomic materials and technology. That hasn't stopped Russia from building a nuclear power plant in Iran, which says it's only interested in atomic energy for peaceful purposes. Defense Minister Ivanov also said this week that Moscow may supply Tehran with more weapons in the future.

Mr. IVANON: (Speaking foreign language)

FEIFER: If Iran wants to buy defensive - I underline defensive - equipments for its armed forces, he said, then why not.

Tehran's recently acquired Tor-M1 missiles are highly advance battlefield weapons mounted on armored vehicles. They were designed by the Soviet Union to protect tank and infantry formations in the conflict with NATO forces in Europe. Defense analyst Pavel Felgenhauer said the missiles are offensive, not defensive weapons.

Mr. PAVEL FELGENHAUER (Defense Analyst): This is a serious development that gives the Iranian military a possibility that they can sort of believe that they can withstand, to some extent, American air supremacy in any kind of clash on the battlefield.

FEIFER: Iran isn't the only U.S. opponent Russia supplies with weapons. Moscow became the largest arms provider to developing countries last year. Its biggest customers are India and China. But Russia also sells weapons to countries like Venezuela and Syria. Israel has accused Syria of supplying Russian rockets to Hezbollah, something Moscow denies. Critics also accused Russia of failing to prevent its arms from getting into the hands of warlords in Africa. Victor Komardin is deputy head of the main state arms export company, Rosoboron Export. He denies accusations Russia is responsible for its weapons getting into the wrong hands.

Mr. VICTOR KOMARDIN (Rosoboron Export): (Through translator) Everything that's blamed on us isn't our fault. All those Kolishnikov automatic riffles, grenades, ammunitions - all that's counterfeit.

FEIFER: Komardin says Moscow's arms exports are simply a legitimate business.

Mr. KOMARDIN: Rosoboron Export was created to administer sales from various Russian manufacturers. That way, we can oversee our exports, compile statistics and allow the government to make sure it's fulfilling its international obligations.

FEIFER: But defense analyst Alexandre Golts says Moscow is using arms sales as a political instrument in its foreign policy.

Mr. ALEXANDER GOLTS (Defense Analyst): (Through translator) Russia is always looking for trump cards in its aims against the West. Special relations with so-called pariah countries is one of those cards.

FEIFER: Washington recently enacted sanctions against Rosoboron Export and other Russian arms companies in a growing standoff that looks set to worsen strained relations between the two countries.

Gregory Feifer, NPR News, Moscow. Transcript provided by NPR, Copyright NPR.