Russia makes the S-400 air defence system a priority in its cooperation with Iran

Russia’s Federal Service for Military-Technical Cooperation has presented the S-400 Triumf as the priority in its exchanges with Iran, as several reports point to initial limited deliveries. Tehran is seeking to rebuild an air defence system tested by US and Israeli strikes, but the Russian system is alternately described as an impenetrable wall and as ineffective protection. Recent engagements in Pakistan and Ukraine have precisely exposed these two faces, at a time when its use by Iran could directly affect air operations around the Persian Gulf.

Russia-Iran cooperation: the S-400 as a priority

Dmitry Shugayev, director of the Russian federal service, explained on 1 September that Iran already possessed the S-300, considered effective but now surpassed by a new generation. Russian-Iranian cooperation also covers military aircraft and small arms. A separate €500 million agreement was reportedly concluded in February 2026 to supply 500 Verba man-portable air-defence launchers, 2,500 missiles and 500 Maugli-2 night-vision devices. According to the document cited by the Financial Times, these deliveries were scheduled between 2027 and 2029.

Several recent reports nevertheless indicate that Iran may already have received several S-400 systems, without confirmation of the number of batteries transferred. Initial equipment may have been tested near Isfahan to protect sensitive infrastructure. Their final location, operational availability and integration into Iran’s air defence network remain unknown. These limited arrivals reportedly followed the destruction of a large part of Iran’s air defence systems during US and Israeli attacks. During the 12-day war of June 2025, Tehran still relied primarily on the Russian S-300 and the Iranian Bavar-373.

Developed by Russia’s Almaz-Antey group as an evolution of the S-300, the S-400 entered service in Russia in 2007. It can engage aircraft, drones, cruise missiles and certain ballistic missiles. Its missile family includes the 9M96E, with a stated range of 40 kilometres, the 9M96E2 at 120 kilometres, the 48N6E3 at 250 kilometres and the 40N6 at 400 kilometres. This latter range places the system well beyond what the US Patriot, the Franco-Italian SAMP/T or Israel’s David’s Sling offer for long-range aerodynamic interception.