Royal Marine Commandos and National Crime Agency officers boarded the sanctioned Russian shadow fleet oil tanker SMYRTOS in the English Channel in the early hours of Sunday 14 June 2026, in the first UK-led operation of its kind. The Ministry of Defence said the six-hour operation was conducted in close coordination with French authorities and was supported by aircraft from the Maritime Air Group, including Chinooks, Merlin Mk4 and Wildcat helicopters, an RAF P-8 aircraft, as well as HMS Sutherland and HMS Ledbury. The SMYRTOS is being held off the south coast of England pending investigation.

Prime Minister Keir Starmer confirmed the operation, saying it 'delivers yet another blow to Russia and reminds those fueling Putin's war in Ukraine that we will not let them hide' [Source: TVP World]. Defence Secretary Dan Jarvis said operations of this kind require skill, professionalism and courage. The UK government said the Prime Minister agreed in March that British Armed Forces and law enforcement officers were able to board shadow fleet vessels in accordance with international law, citing UNCLOS Article 110, which permits a warship to exercise a right of visit to verify the flag where there are reasonable grounds to suspect a vessel is without nationality [Source: GOV.UK (UK Government)].

The SMYRTOS operation marks the first time the UK has independently led a boarding of a shadow fleet vessel, though the UK has previously provided RAF and Royal Navy capabilities in support of US and French operations targeting such ships. The UK government said Russia's shadow fleet comprises over 700 vessels, which are responsible for carrying 75% of Russia's sanctioned oil, and that the UK has already sanctioned over 500 shadow fleet vessels [Source: GOV.UK (UK Government)]. The government also noted that over 72% of shadow fleet tankers are more than 15 years old and that there have been more than 50 incidents involving these vessels.

Russia's oil and gas revenues fell by 24% year-on-year in 2025, according to the UK government. No listed shipping, insurance, or oil company has been publicly linked to the SMYRTOS in reporting available at the time of the operation.

Sources: BBC News, The Guardian, Bloomberg, CNBC, GOV.UK (UK Government), TVP World, TheJournal.ie