Iran has reportedly showcased Russian-built S-300 surface-to-air missile tubes and radar equipment during the Army Day Parade in Tehran.
Delivered as part of a contract signed by the two countries last year, Russia delivered the first batch of the new advanced S-300 air defence system to Iran.
Iran originally signed an $800m contract with Russia in 2007 for the supply of five S-300PMU-1 systems, but it was scrapped in 2010 following a fourth UN Security Council arms embargo on the Middle Eastern country.
However, followed by the deterioration of relationship with both the US and Europe, Russia lifted the ban last April.
The S-300 is a long-range surface-to-air missile system developed to defend Russia against aircraft, and cruise and ballistic missiles. The system has undergone multiple modifications since the first deployment by the then USSR in 1979.
The surveillance radar tracks objects over a range of 300km and alerts the command vehicle, which directs the engagement radar to launch missiles, according to a report by the BBC.
The engagement radar guides the missiles to the target. It has the capability to simultaneously guide 12 missiles and engage six targets.
The launch vehicle can fire two missiles vertically within three seconds to a maximum range of 150km.
Different S-300 variants are currently in use with Algeria, Armenia, Azerbaijan, Bulgaria, China, Russia, Ukraine, Venezuela, and Vietnam.