British authorities have formally detained a Russian shadow fleet vessel following its interception in the Channel by Royal Marine commandos and National Crime Agency officers on Sunday.
This marks the first UK-led operation to seize a sanctioned ship.
Transport Secretary Heidi Alexander confirmed the formal detention Monday, issuing an order that prevents the vessel from leaving UK waters.
The Smyrtos, which sailed under the flag of Cameroon but is deemed "stateless" by the UK government, remains anchored off Weymouth, Dorset.
It is accompanied by Royal Navy vessels HMS Sutherland and HMS Ledbury, which participated in the operation.
Ms Alexander stated: "Today, I took the decision to detain a sanctioned shadow fleet vessel travelling through the Channel, carrying the Russian oil which helps fund Putin’s barbaric war in Ukraine."
A 38-year-old Indian national has also been arrested on suspicion of sanctions offences, and it is understood another 24 Georgian and Indian crew members remain on board and are assisting the investigation.
Moscow’s shadow fleet is reported to be made up of more than a thousand ageing tankers which illicitly ship oil and other goods out of Russia by flying the flags of other countries, with the aim of evading sanctions imposed by the West since the invasion of Ukraine began.
British forces have already been involved in tracking shadow fleet vessels for several years and have supported operations by other countries to seize the ships.
But Sunday’s operation was the first time UK personnel had seized a sanctioned vessel directly as the Government tries to force shadow fleet ships to take longer, more expensive routes or risk being intercepted.
On Sunday, Sir Keir Starmer revealed that British armed forces had untercepted a Russian shadow fleet vessel in the Channel in the early hours of Sunday.
The vessel Smyrtos will be provisionally moved to an anchorage off the south coast of England and monitored for any environmental or safety concerns.
According to the MoD, the operation was supported by aircraft from the Maritime Air Group (Chinooks, Merlin Mk4 and Wildcat), an RAF P-8 aircraft, and HMS Sutherland and HMS Ledbury.
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