The ship in the incident is VAYU 1, sanctioned for transporting oil from Russia. Ship tracking data shows that VAYU1 was about 6 nautical miles off the coast of Dover.
The ship was recorded at this location on March 26, one day after the British government announced that it allowed the country's armed forces to inspect sanctioned vehicles when passing through British waters.
Data from MarineTraffic shows that the VAYU 1 ship, flying the Cameroon flag, departed from the Russian city of Murmansk on March 10 and was full of cargo.
The ship first entered British waters at 12:39 pm (GMT) on March 26 and was discovered by a user on social network X. The ship's final destination was not announced on the tracking system.
The British government has put VAYU 1 on the sanctions list since May 2025 due to suspicions related to Russian oil transportation.
On March 25, the British government announced that it had allowed its forces to board ships to inspect ships sanctioned when passing through British waters.
However, it is still unclear what the definition of "British waters" includes. This concept could be British territorial waters extending up to 12 nautical miles from the coast or exclusive economic zone (EEZ) extending up to 200 nautical miles from the coastline.
Analysis shows that VAYU 1 was in British territorial waters for at least 5 hours and 30 minutes and had a total of 29 hours in British EEZ.
The most recent location of this oil tanker was recorded to be about 40 nautical miles south of Plymouth, still within British EEZ.
When asked about the incident of ship VAYU 1 entering British waters and planning to intervene, the British Ministry of Defense said: "All enforcement actions are considered in each case, in accordance with international law and domestic law.
This agency also noted that it will not provide information in real time because this may affect the ability to implement measures against sanctioned ships.
According to Professor Kevin Rowlands - Royal United Services Institute (RUSI), the identification and tracking of ships is quite easy because the list of "dark fleets" is widely known and the surveillance of British waters is relatively comprehensive.
Getting on board depends on many factors such as the type of ship, location and weather conditions. British forces can approach by boat or more commonly by helicopter.
The British Navy has inspection teams including sailors and marines, trained to board safely, work with the crew, search ships, check papers and, if necessary, escort ships to British ports.
