Ukrainian forces have regained control from Russia of several gas and oil offshore drilling platforms close to Crimea, Ukraine's military intelligence (GUR) said on Monday.
It said on the Telegram messaging app that Kyiv's forces had retaken the drilling platforms known as the "Boiko Towers" in a "unique operation".
It said the platforms had been occupied since 2015 by Russia, which seized and annexed Crimea in 2014, and had been used by Moscow for military purposes since the start of Russia's full-scale invasion on Ukraine in February 2022.
Russia did not immediately comment on the report. Reuters was unable to independently verify the GUR's information.
"For Ukraine, regaining control of the Boiko Towers was of strategic importance and, as a result, Russia lost the ability to use them for military purposes," GUR said in a video posted on Telegram.
"Russia has been deprived of the ability to fully control the waters of the Black Sea, and this makes Ukraine many steps closer to regaining Crimea," it said.
During the operation, GUR said, there was a clash between Ukrainian special forces on boats and a Russian fighter jet, which was damaged and forced to retreat.
GUR also captured other "valuable trophies" such as helicopter munitions and a radar system that can track the movement of ships in the Black Sea, it said.
Before Russia seized the Crimea peninsula, Ukraine extracted a significant part of its natural gas from the Black Sea shelf, providing gas not only for Crimea but also to mainland regions of Ukraine.
(Reporting by Anna Pruchnicka and Pavel Polityuk, Editing by Timothy Heritage)