British forces on Sunday intercepted a sanctioned oil tanker belonging to Russia's shadow fleet in the English Channel, the defense ministry said.

The six-hour operation in the early hours was supported by aircraft, including Chinook helicopters, and navy vessels such as the frigate HMS Sutherland.

“In the first U.K.-led operation of its kind, the vessel SMYRTOS was boarded by Royal Marine Commandos and specially trained law enforcement officers from the National Crime Agency, despite Russia's best efforts to evade sanctions and continue fueling its barbaric war with Ukraine,” the ministry statement said.

The vessel will now be moved to an anchorage off the south coast of England and monitored, it added.

“Russia relies on its shadow fleet to fund their conflict in Ukraine and our interdiction delivers a blow to Putin's illegal war,” said defense minister Dan Jarvis.