TEHRAN. - Iran demands Russia to compensate for the unfulfilled contract on the supplement of anti-aircraft missile systems S-300, Iranian Defense Minister Ahmad Vahidi announced.

The amount of the contract is estimated $800 million.

Iran sued Russia in the international arbitration in September 2011.

According to the minister, the lawsuit is still in the process of discussion, MIGnews agency reports.

In August 2010 Dmitry Medvedev, then Russian president, signed an order prohibiting to supply Iran with S-300 anti-aircraft missile systems because of international sanctions.