In May, Russia fired over 300 Iranian-made Shahed drones, also known as kamikaze drones, at Ukraine. It is the most intensive use of the drones so far during the Ukraine war, according to the British Ministry of Defense.
Western countries have tried to pressure Iran to stop sending drones to Russia, but this has had limited effect.
- Iran describes the West's reactions as hysterical or as an attempt to keep Iranian products off the market, says SVT's foreign reporter Carl Fridh Kleberg.
Sanctioning drone exports has also proved difficult, mainly because of one geographical detail: the Caspian Sea.
Watch SVT's foreign reporter explain why Russia uses the Iranian drones in the video above.