Russian air defence will protect Iran
He said the contract for the system was signed a few years ago.
Vladimir Sotnikov from the Institute of World Economy and International Relations said some S-300 anti-missile systems had already been delivered to Tehran.
“This was probably a part of past agreements between the Russian government and the government of Iran,” Sotnikov said.
The S-300 targets planes, helicopters and incoming missiles. It is not banned by any international conventions.
Moscow has yet to confirm the terms of the deal.