S-300 missile system
S-300 missile systemReuters

Russia and Iran have formally reached a deal for Moscow to deliver Tehran advanced S-300 missile systems, deputy foreign minister Mikhail Bogdanov told RIA Novosti on Wednesday afternoon. 

"As things stand now, this topic is closed," Bogdanov stated. "We have reached full understanding on the matter together with our Iranian partners."

"The question has been fundamentally solved," he stressed. "The rest is just technical details." 

A high-ranking official in the Russian Foreign Ministry told the daily that the exact number of S-300 missiles, to be delivered later this year, has been specified in the contract. The number is said to be four divisions instead of three, according to RT, but this has not yet been confirmed. 

The S-300 is a long range surface-to-air missile – manufactured by the Russian firm Almaz – designed to intercept aircraft and cruise missiles, and its most advanced models can also target ballistic missiles.

The announcement follows less than 24 hours after Tehran claimed that a deal was close with Moscow, and likely to be finalized by next week. 

A previous Russian contract to sell Iran the S-300 system by 2010 fell through due to diplomatic pressure surrounding sanctions on the Islamic Republic. However, with the signing of the recent nuclear deal - which includes an astonishing commitment to help Iran protect its nuclear facilities against an attack - Moscow has revived the sale.