A top Russian weapons maker said Thursday that the S-300 air defence missile systems made for Iran had been dismantled and disposed of following Western pressure to shelf the contract.

"The hardware that was destined for Iran no longer exists," general director of Russian weapons manufacturer Almaz-Antey Vladislav Menshchikov told reporters.

"We have dismantled it completely. Separate elements, what could be used have been used," he said, adding that some other parts have been destroyed. "This is absolutely reliable information," he was quoted as saying by the Interfax news agency.

Russia's contract to sell its ally Iran the sophisticated ground-to-air-missiles was estimated to be worth some $800 million (600 million euros).

In 2010, Russia cancelled the contract after coming under strong US and Israeli pressure not to go ahead with the sale of the weapons system, drawing vehement protests from Tehran.

Russia, which has been a strong ally of Iran and built the Islamic republic's first nuclear power plant in the southern city of Bushehr, said it would reimburse Iran for its downpayments on the deal.