MOSCOW, June 3 (Xinhua) -- Russia will not supply Iran with offensive weapons such as battle tanks and bombers due to UN Security Council sanctions against Iran, the CEO of State Corporation Rostec Sergey Chemizov said Friday.

"While there are UN Security Council sanctions against Iran, Russia will only supply weapons which are not covered by sanctions, for example, the air defense missile system S-300. We have never broken international agreements and won't do so," said Chemizov in an interview with Russian newspaper Kommersant.

Russia and Iran have already signed a contract on delivering a S-300 air defense system. The first batch has been already unloaded.

Chemizov added that Russia will deliver four divisions of the S-300 to Iran by the end of this year.

The S-300 system was designed for the air defense of large industrial and administrative facilities, military bases and control of airspace against enemy aircraft.

Rostec is a Russian state corporation established in late 2007 to promote the development, production and export of hi-tech industrial products for the civil and defense sectors.