Tehran is due to withdraw its lawsuit against Moscow once the first Russia-produced S-300 air defense system is delivered to Iran, Russian Deputy Prime Minister Dmitry Rogozin said Friday.

VLADIVOSTOK (Sputnik) — According to Rogozin, the "unconditional withdrawal" of the lawsuit is one of the conditions for delivery of the S-300 systems.

"[Iran] is due to withdraw [the lawsuit] after delivery of the first unit," Rogozin told reporters, adding that this was due to happen soon, following the completion of the manufacturing process.

Moscow and Tehran signed an $800-million deal for the delivery of five S-300 missile systems in 2007. In 2011, Iran sued Russia after Moscow suspended the contract in 2010, citing a UN Security Council resolution that placed an arms embargo on Tehran over its nuclear program.

In April 2015, Russian President Vladimir Putin lifted the S-300 delivery ban, shortly after the six world powers and Iran reached a framework nuclear agreement to remove all economic sanctions against Tehran in exchange for guarantees of the peaceful nature of its nuclear activities.