Crimea, which was annexed by Moscow in 2014 and is home to Russia's Black Sea Fleet, has been extensively targeted by Ukrainian drones and missiles, putting Russia on the defensive.

"An enemy missile corvette was destroyed" during the night, Ukraine's military intelligence agency said in a statement online. Russia made no immediate comment.

The Ukraine agency named the vessel as the Ivanovets and claimed the ship was worth up to $70 million.

In a night-vision video it published purporting to show the attack, a small vessel is seen approaching the Russian ship, followed by a large explosion and the warship then appearing to start rolling over and sinking.

AFP was not able to independently verify the footage or Ukraine's account of the incident.

Kyiv said it happened near Lake Donuzlav -- a lake that flows into the Black Sea on the western coast of Crimea.

Ukraine also claimed a Russian search and rescue operation after the attack was "not successful".

While Moscow made no immediate statement, a Russian Telegram account with army links said Ukraine had attacked in the area with nine naval drones at night.

"Four of them were discovered by Russian sailors patroling Lake Donuzlav. They opened fire on them," it said, adding that one boat was "damaged."

On Wednesday, Russia said it destroyed 20 Ukrainian missiles over the Black Sea and Crimea.

Moscow annexed Crimea in 2014 and in February 2022 invaded Ukraine from several directions, including from the Black Sea peninsula.