British Prime Minister Keir Starmer said Sunday that armed British forces boarded and detained a sanctioned tanker suspected of being part of the Russian "shadow fleet," shipping oil in violation of international sanctions over Moscow's war on Ukraine. This was reported by Qazaqyia.kz citing Associated Press.
According to the Defence Ministry, Royal Marine commandos rappelled from helicopters onto the vessel, the Smyrtos, in the English Channel, in what the ministry called "the first U.K.-led operation of its kind." The vessel will be held and monitored off the south coast of England for investigation. The operation was carried out "in close coordination" with French authorities, who have previously intercepted a number of vessels linked to the "shadow fleet."
Starmer said the operation "delivers yet another blow to Russia and reminds those fueling the war" that sanctions have consequences. He added that it shows "our sanctions have teeth."
The U.S. estimates Russia's shadow fleet consists of around 600 vessels, often using old, poorly insured ships to evade sanctions. The fleet is believed to help Russia continue exporting oil and finance its war.
The British government has previously taken measures against the shadow fleet, including sanctions and maritime inspections. However, this is the first time British forces directly boarded and detained a vessel in such an operation.
French authorities had previously intercepted several shadow fleet vessels in 2024 and 2025, with the most recent detention in November 2025 when French naval forces stopped a sanctioned oil tanker in the English Channel.
The British action drew international support. U.S. Secretary of State Antony Blinken said, "We commend the United Kingdom's efforts to enforce sanctions." The European Union also called the operation "an important step in ensuring the effectiveness of sanctions."
The issue of Russia's shadow fleet has been a focus of international attention in recent years. After Russia's invasion of Ukraine in 2022, Western countries imposed a price cap and sanctions on Russian oil. However, Russia continued selling oil to other countries using old vessels to bypass these restrictions.
Experts say operations to detain shadow fleet vessels help increase the effectiveness of sanctions but cannot fully solve the problem, as Russia may find other ways to transport oil.
The British government has not yet released details of the operation but said the investigation is ongoing. It is unclear whether the crew of the Smyrtos has been arrested.
This incident demonstrates Britain's determination to strictly enforce sanctions against Russia. Starmer said, "We will continue to oppose any attempts to finance Russia's war machine."