Israeli Prime Minister Binyamin Netanyahu is scheduled to hold talks with Russian President Dmitry Medvedev today in Moscow.
Netanyahu says he will urge Medvedev to back "crippling sanctions" against Iran over its nuclear program.
Russia has said it would not oppose fresh UN sanctions against Iran after Tehran announced it was enriching uranium to greater purity.
But in a move that will concern Israel, a leading member of Russia's Security Council said sanctions were no reason to stop it shipping an order of S-300 antiaircraft missiles to Iran.
"This deal is not restricted by any international sanctions, because the talk is about deliveries of an exclusively defensive weapon," Vladimir Nazarov, deputy secretary of Russia's Security Council, said ahead of Netanyahu's visit.
compiled from agency reports