In the early morning in the English Channel, British Royal Marines together with employees of the National Crime Agency (NCA) boarded the tanker SMYRTOS — a shadow fleet vessel carrying Russian oil in circumvention of sanctions. The operation lasted six hours and was the first of its kind at the UK's initiative.
How the evasion scheme works
SMYRTOS departed from the Russian oil terminal Ust-Luga on the Baltic on June 1st, heading west — presumably carrying cargo to buyers in Asia. The vessel is registered under a Cameroonian flag, but this flag is considered forged.
The owner and commercial manager of the tanker since February 2025 is Daira Shipping Ltd, registered in the Seychelles, while the ISM manager is Crest Maritime Pte Ltd from Singapore. This very multilayered ownership structure is a typical shadow fleet tactic: complex ownership schemes, flags of convenience, and other tactics mask the origin of cargo.
"This operation has delivered another blow to Russia and should remind those who finance Putin's war in Ukraine: you cannot hide."
UK Prime Minister Keir Starmer — in a post on social media after the operation's completion
What was involved and why so many forces
The operation was supported by Maritime Air Group helicopters (Chinook, Merlin Mk4, and Wildcat), an RAF P-8 reconnaissance aircraft, as well as ships HMS SUTHERLAND and HMS LEDBURY. The scale of forces deployed is explained not only by the tanker's size — it is symbolic: London is demonstrating that it is willing to bear real costs to enforce sanctions compliance.
Legal basis: where exactly they found the "hook"
For more than a year, Britain searched for a legal mechanism for such operations. The legal basis for the interception was Article 110 of UNCLOS, which allows a warship to check the flag of a vessel if there are grounds to believe it has no nationality. If a vessel is recognized as "stateless," Britain can apply the provisions of domestic legislation — in particular, the sanctions provisions of the Russia (Sanctions) (EU Exit) 2019 regulation. The Prime Minister authorized armed forces and law enforcement personnel to board shadow vessels in March.
The scale of the problem
One interception is a drop, but the figures provide understanding of the size of the "ocean." The shadow fleet comprises over 700 vessels and carries 75% of Russian sanctioned oil. Over 72% of shadow fleet tankers are older than 15 years — meaning they pose increased environmental risks. Meanwhile, sanctions pressure is gradually yielding results: in the first quarter of 2025, vessels listed on British sanctions lists transported 1.6 billion dollars less Russian oil compared to the same period last year. Russia's oil and gas revenues fell 24% year-on-year.
The tanker has been moved to an anchorage off the south coast of England — where authorities will monitor potential environmental and security threats during the investigation.
The key question is not whether SMYRTOS will appear in court — but whether this operation will become a precedent for systematic work: if Britain carries out 5–10 similar interceptions over the coming months, insurance markets and shadow fleet operators will receive a real signal of risk. If the operation remains a single demonstration — the fleet of 700 vessels will simply adjust its routes.
