The UK has conducted boarding operations against a Russian ‘shadow fleet’ ship for the first time. The vessel, the crude oil tanker Smyrtos, was interdicted in the English Channel in the early hours of 14 June.
According to a UK government statement, Royal Marines Commandos and National Crime Agency (NCA) law enforcement personnel undertook the boarding task.
In a six-hour operation, the boarding was supported by Chinook, Merlin Mk4, and Wildcat helicopters from the combined Maritime Air Group; a UK Royal Air Force Poseidon P-8A maritime patrol and reconnaissance aircraft (MPRA); and the UK Royal Navy’s Type 23 frigate HMS Sutherland and Hunt-class mine warfare vessel HMS Ledbury. According to the statement, the operation was conducted in close co-ordination with France.
Naval News understands that such co-ordination enabled operational deconfliction, as Smyrtos was being tracked by both countries.
The statement added that, while investigations continue, the vessel will be held at an anchorage off the UK’s south coast and monitored for any environmental or safety concerns.
Ledbury is involved in providing security around the anchorage.
According to marinetraffic.com, Smyrtos is currently located east of Portland Bill.
“The enforcement action against this vessel took place in international waters and was carried out in accordance with domestic and international law,” the statement said.
Initially, Sutherland had been observing the vessel from distance in the days preceding the operation. Naval News understands the interception eventually took place around 25 miles off the Isle of Wight.
This first UK operation against the ‘shadow fleet’ follows authorisation being given in late March for UK forces to undertake such activities. At that time, the UK Ministry of Defence (MoD) said the legal basis for action and the relevant military options had been aligned, meaning the UK was ready to act and was signalling intent to do so.
Such readiness will have encompassed preparing the required specialist units to conduct interdictions, including potentially encountering unco-operative crews. Such interdiction and boarding operations are known formally as vessel board, search, and seize (VBSS) tasks. Naval News understands the ship’s crew in this instance co-operated with the VBSS requirements.
The BBC reported on 15 June that an individual was subsequently arrested, by NCA officers, on suspicion of sanctions offences.
Russia allegedly uses ‘shadow fleet’ shipping – which consists of commercial ships sailing without a valid national flag – to support oil exports, in contravention of international sanctions put in place following its invasion of Ukraine in February 2022.
“Russia relies on its ‘shadow fleet’ to fund its conflict in Ukraine, and our interdiction delivers a blow to [Russian president Vladimir] Putin’s illegal war,” Dan Jarvis, the UK’s Secretary of State for Defence, said in the government statement.
The statement noted that the estimated 700-ship ‘shadow fleet’ carries 75% of Russia’s sanctioned oil; it added that the UK has sanctioned over 500 of these vessels, and that Russian oil and gas revenues fell by 24% year-on-year in 2025.
Smyrtos is one of the UK-sanctioned vessels, the statement said.
In conclusion, it continued, “Today’s action sends a clear message to Russia that the UK will use the full range of legal tools available to enforce those sanctions and protect our security.”
Under Article 110 of the 1982 United Nations Convention on the Law of the Sea (UNCLOS) treaty, a warship may be employed to exercise a right of visit in order to verify a vessel’s flag status when there are reasonable grounds to suspect the vessel is without nationality. If such a determination is made regarding a suspect vessel, boarding operations for investigative purposes may also be conducted.
In conducting boardings and subsequent investigations, different countries may have various legislative tools available to use. The BBC has reported previously that one such tool for the UK is its 2018 Sanctions and Money Laundering Act.
Naval News Comment
Following a difficult week in UK defence circles, due to continuing, national-level political debate about defence funding, the operation demonstrated – to any observer – the UK’s continued readiness and capability at sea to be able to conduct high-end operations designed to deter risks to national and international interests.
Russia’s use of its own naval vessels to escort ‘shadow fleet’ shipping in the English Channel/North Sea/Baltic Sea region, plus the routine presence of Russian naval ships in and around UK waters (which the UK government has said previously has increased by 30% since 2024), is a factor to consider in any such interdiction activities.