Russia announced Monday that it has agreed to push on with a deal to deliver S-300 missile systems to Iran after Moscow halted an earlier agreement due to UN sanctions previously imposed on Tehran.

Russia announced Monday that it has agreed to push on with a deal to deliver S-300 missile systems to Iran after Moscow halted an earlier agreement due to UN sanctions previously imposed on Tehran.

"The contract between Russia and Iran for delivery of S-300 missile systems is back in force," the state-run Russian Technologies corporation said in a statement, adding that the two sides had "signed a contract".  

Moscow in April lifted a ban on selling the missile systems to Iran, ahead of Tehran sealing a final historic deal with world powers in July to curb its nuclear program.

The decision sparked condemnation from the Zionist entity and concern from Washington, as it came before the lifting of the sanctions by the UN Security Council.

Russia argues that the missile system is exclusively defensive and does not even fall under the sanctions.

Moscow blocked deliveries of the surface-to-air missiles to Tehran in 2010 after the UN Security Council imposed sanctions on Iran over its alleged nuclear program barring hi-tech weapons sales.  

Iran then filed a $4-billion suit at an arbitration court in Geneva for the cancellation of the $800 million order by Russia.

Moscow says it has now offered Tehran more modern versions of the weapons but has yet to announce publicly when they will be delivered.

Russian Technologies said the Islamic Republic had agreed to drop its legal claims against Moscow after the "first part" of the contract is fulfilled.