British armed forces have intercepted a sanctioned Russian-linked oil tanker in the English Channel, marking the first time the United Kingdom has led an operation aimed at disrupting the so-called “shadow fleet” that helps generate revenue for Russia’s war in Ukraine.

The vessel, Smyrtos, which was sailing under a Cameroon flag, was boarded in the early hours of Sunday by Royal Marine Commandos and officials from the National Crime Agency (NCA). The operation was supported by Chinook helicopters, surveillance aircraft, a Royal Navy frigate and a minehunter.

The British government released footage showing commandos descending onto the tanker from helicopters, while NCA officers inspected documents and conducted searches onboard.

Prime Minister Keir Starmer hailed the operation as a significant step in efforts to counter Russia’s sanctions evasion network.

“This successful operation delivers yet another blow to Russia and reminds those fuelling Putin’s war in Ukraine that we will not let them hide,” Starmer said in a post on X.

Ukrainian President Volodymyr Zelenskyy welcomed the action, thanking Britain for detaining the vessel. Kyiv has repeatedly urged its allies to intensify enforcement measures against Russia’s shadow fleet, which Ukraine says plays a key role in financing Moscow’s military campaign.

In a post on X, Zelenskyy called for tougher action across Europe, including legal measures that would allow authorities not only to detain tankers suspected of violating sanctions but also to confiscate the oil they carry.

“Europe urgently needs to take legislative steps to enable not only the detention of tankers and restrictions on oil shipments, but also the confiscation of the oil they carry. This will certainly help bring peace closer,” Zelenskyy said.

The interception highlights growing international efforts to target the maritime network Russia is accused of using to circumvent Western sanctions imposed following its invasion of Ukraine.