Dozens of oil tankers sanctioned by the UK in response to Russia's war in Ukraine have sailed through the English Channel this month despite defence officials vowing to take "assertive action".
Since its full-scale invasion of Ukraine, Russia has used hundreds of ageing tankers with obscured ownership - known as the shadow fleet - to evade sanctions on its oil exports.
The BBC understands that the UK government received legal assurances earlier this month that such vessels can be detained. Yet 42 sanctioned tankers tracked by BBC Verify passing through the English Channel did so after that advice was received.
Among them was the Sofos - a tanker sanctioned by the UK Foreign Office in May 2025. It moved through the Channel after travelling from Venezuela and is now near the Russian city of St Petersburg.
Ship-tracking data shows the Sofos loaded oil in Russia in mid-November, before travelling to Turkey and then to Venezuela, where it switched off its tracking signal. Satellite imagery later placed it at Venezuela's Jose oil terminal on 22 and 23 December, before its signal reappeared outside the country's waters on 26 December.
