Moscow, Russia (CNN) -- Russia blocked weapons sales to Iran on Wednesday because of U.N. sanctions against the Islamic republic.
President Dmitry Medvedev signed a decree that prohibits "the transit across Russia, including by air, the removal from Russia to Iran, and the transfer to Iran outside Russia of any combat tanks, armored personnel carriers, large-caliber artillery systems, warplanes, attack helicopters, military vessels, missiles or missile systems as defined by the United Nations Register of Conventional Arms, S-300 surface-to-air missile systems, or materiel and spare parts used for all of the above."
The decree was published on the Kremlin website.
This comes after Russian media reports that Moscow has decided not to sell S-300 air defense missile systems to Iran because they are subject to U.N. Security Council sanctions,
"A decision has been made not to supply S-300s to Iran as they are definitely subject to the sanctions," Armed Forces Chief of Staff Gen. Nikolai Makarov said, according to the state-run RIA-Novosti news agency. "There has been an instruction from the country's leadership to stop the deliveries, and we are obeying it."
Makarov didn't give a definite response on whether the contract between Iran and Russia on those deliveries will be terminated. However, he said, "we'll see. Everything depends on Iran's behavior," according to RIA-Novosti.
Russia froze the contract with Iran on the S-300 missiles this year after the latest U.N. Security Council resolution imposing sanctions on Iran.
CNN's Max Tkachenko contributed to this report.