June 14 (UPI) -- British forces intercepted an oil tanker from Russia's shadow fleet on Sunday, an effort the Ministry of Defense said "will disrupt [Russian President Vladimir] Putin's war chest" in the conflict with Ukraine.

A release from the ministry said the operation took place in the English Channel, south of the British coast. British commandos and officers from the National Crime Agency boarded the tanker Smyrtos in an effort that took 6 hours.

Russia's shadow fleet of more than 700 vessels carries more than 75% of the country's oil currently sanctioned as a result of the war in Ukraine. Much of the money earned from the oil goes toward funding Russia's four-year invasion of Ukraine.

British Prime Minister Keir Starmer said the interception of the tanker was "yet another blow to Russia and reminds those fueling Putin's war in Ukraine that they cannot hide." Starmer released a video from the operation in a post on X.

Ukrainian President Volodymyr Zelensky issued a statement thanking Britain for its "principled resolved" in the operation.