Ukraine claimed it carried out an underwater drone strike on Dec. 15, the first such attack in maritime warfare, that critically damaged a Russian Kilo-class attack submarine at the Russian port of Novorossiysk,

Ukraine has used long-range drones to attack Russian oil platforms as it expands its strikes on the country's energy sector.

Ukraine has claimed a historic naval success, saying its 'Sub Sea Baby' underwater drones damaged a Russian submarine at the Black Sea port of Novorossiysk.

The Russian submarine was allegedly carrying Kalibr cruise missiles, which Russia has used in devastating strikes on critical infrastructure and military targets across Ukraine. The SBU said the submarine was “put out of action” as a result of the blast. The FT could not independently verify the claim.