A recent Ukrainian strike on an Iranian vessel in the Caspian Sea has drawn concerns that Russia's war in Ukraine and the war in Iran are becoming entangled.

Ukraine has said the ship was carrying military equipment from Iran to Russia. Iranian state media, citing Iran's ambassador to Russia, Kazem Jalali, reported that the cargo vessel "Anna" was anchored approximately 5 kilometers (3 miles) from the entrance of the Volga River when it was attacked by drones causing an explosion. One sailor was reported killed.

Iran summoned Ukraine's charge d'affaires and described the incident as an act of aggression.

Ukrainian President Volodymyr Zelenskyy, meanwhile, said Ukrainian forces had carried out successful long-range strikes against a Russian warship and vessels that Kyiv says were transporting military cargo.

Ukraine has long accused Iran of helping Russia wage war through the supply and development of Iranian-designed drones.