Britain Detains Russian Shadow Fleet Tanker in First Major Channel Operation

Britain has detained a sanctioned oil tanker suspected of belonging to Russia’s “shadow fleet” in the English Channel , marking the first UK-led maritime operation aimed at disrupting oil revenues that help finance Moscow’s war in Ukraine.

The vessel, Smyrtos , sailing under a Cameroonian flag, was intercepted in a six-hour operation involving Royal Marine Commandos , National Crime Agency (NCA) officers, Royal Navy warships and Royal Air Force aircraft. Video released by the UK government showed commandos rappelling from helicopters onto the tanker before investigators searched documents on board. The operation was personally authorised by Prime Minister Keir Starmer .

According to British authorities, the tanker had departed from Russia’s Baltic port of Ust-Luga and was heading toward Port Said in Egypt. Reports indicate it was carrying about 700,000 barrels of Russian crude oil when intercepted. The vessel is now anchored off England’s south coast while investigations continue.

The mission involved HMS Sutherland, HMS Ledbury, Chinook, Merlin and Wildcat helicopters, and surveillance aircraft. British officials said the action was conducted in coordination with French authorities and in accordance with domestic and international law.

Western governments accuse Russia of operating a vast shadow fleet of ageing tankers that use opaque ownership structures, false registrations and ship-to-ship transfers to bypass sanctions. The UK says nearly 600 vessels linked to the network have already been sanctioned, while broader estimates place the fleet at more than 700 ships worldwide .

Starmer described the interception as “another blow” to Russia’s war machine. Ukrainian President Volodymyr Zelenskyy thanked Britain and urged European nations to adopt stronger measures, including the confiscation of oil cargoes carried by shadow-fleet vessels. Officials said several similar tankers altered their routes after the operation, highlighting growing pressure on Russia’s sanctions-evasion network.