Russia and Iran have signed this week a memorandum on the implementation of the agreement for the delivery of the Russian S-300 missile defense systems to Iran, a senior official from the Russian Federal Service for Military-Technical Cooperation said Thursday.

"This week, a memorandum on the implementation of the agreement to supply Russian S-300 missile defense systems to Iran has been signed. It is a kind of a 'roadmap,'" the official told RIA Novosti.

He added that the memorandum does not specify a specific time frame, the number of systems to be delivered or prices.

In 2007, Russia and Iran signed an $800-million deal for the delivery of five S-300 battalions. Moscow suspended the deal after the UN Security Council issued an arms embargo on Tehran amid suspicions that it was creating a nuclear weapon.

Russian President Vladimir Putin lifted the ban on S-300 deliveries in April, shortly after the P5+1 group of international negotiators and Iran reached a framework nuclear agreement to remove all economic sanctions against Tehran in exchange for its pledge to cut back uranium enrichment and the number of centrifuges in the country.