Dozens of sanctioned Russian tankers navigate Channel despite UK pledge of ‘assertive’ action

Dozens of oil tankers authorized by the UK in response to Russia’s war in Ukraine have sailed through the English Channel this month despite defense officials vowing to take “assertive action”.

Since its full-scale invasion of Ukraine, Russia has used hundreds of aging tankers with invisible ownership – known as the shadow fleet – to avoid sanctions on its oil exports.

The BBC understands that the UK government received legal assurances earlier this month that such vessels could be detained. However, the 42 authorized tankers tracked by BBC Verify transiting the English Channel did so after receiving the advice.

Among them is Sofos – a tanker authorized by the UK Foreign Office in May 2025. It moved to the Channel after traveling from Venezuela and is now near the city of St Petersburg in Russia.

The ship’s tracking data shows the Sofos loaded oil in Russia in mid-November, before traveling to Turkey and then to Venezuela, where it switched off its tracking signal. Satellite images later placed it at the Jose oil terminal in Venezuela on 22 and 23 December, before its signal reappeared outside the country’s waters on 26 December.

The Nasledie, a tanker over 20 years old, also entered the Channel in January. The ship was sanctioned by the UK in May 2025 and according to Anna Zhminko, an analyst at the Maritime Intelligence firm Vortexa, has been part of the shadow fleet since 2023.

In November the ship had a change, changed its name from Blint and transferred to a Russian registry after falsely flying under the flag of Comoros. It left Russia in late December and a few days after The BBC reports on UK legal advice it entered the Channel carrying about 100,000 tons of Urals crude oil, Russia’s oil benchmark.

The shadow fleet has helped Russia mitigate the impact of an embargo imposed on oil exports from 2022 and has helped prop up an economy battered by Western sanctions.

In January, Foreign Secretary Yvette Cooper said that the British government ready to “tighten the chokehold” on Russia and take new “assertive actions” against shadow fleet vessels. His comments came after officials were told that troops could board and seize tankers under the Sanctions and Money Act 2018.

While the UK aided the US forces in a tanker was seized near Iceland in early January and France in the Mediterranean on ThursdayBritish troops have yet to independently seize any shadow fleet vessel.

This is despite BBC Verify identifying six tankers operating in the Channel under false flags since the start of January. This means that the ships are not registered in the states they publicly claim to be registered.

Dame Emily Thornberry, chairman of Parliament’s Foreign Affairs Select Committee, said she was “very disappointed” that the ships had not been intercepted.

“I think in order to give the right support to Ukraine, we need not only sanctions that appear on paper, but we need to make sure that we mean it and that we implement the sanctions,” he said.

Mike Martin, a Liberal Democrat MP and former British Army officer, asked why the UK was reluctant to board tankers independently, saying the UK’s Royal Marines were trained and equipped for such operations.

“It is not very difficult to project a force 12 miles from the Straits of Dover,” he said. “It’s not that hard to get on a tanker.”

Russia also appears to have reacted to the UK’s pledge to take tougher action against the shadow fleet. On January 20 the Times reported that a warship was escorting the sanctioned tanker General Skobelev through the Channel.

And on January 15, Russian Foreign ministry spokeswoman Maria Zakharova said the Kremlin would view any detention of the tankers as a violation of international law that could be seen as “damaging Russia’s interests”.

In a statement to BBC Verify, a spokesman for the Ministry of Defense said: “Deterring, disrupting and degrading the Russian shadow fleet is a priority for this government. Together with our allies, we have increased our response to shadow vessels – and we will continue to do so.”

Other tankers sanctioned by the US and EU, but not the UK, also sailed through the Channel during January.

BBC Verify has identified a ship that has taken extreme measures to avoid detection and has been labeled by maritime experts as “the darkest of the dark fleet”.

Arcusat – which was previously authorized by the US as Tia, before changing its identity in 2024 – passed through the Channel on 8 January before being stopped by German federal police and turned away before it entered the country’s waters.

Last year, it got a new IMO number in a move that analysts say is almost unheard of. The unique code identifies the vessel and must be associated with a vessel for life, regardless of name or ownership changes.

Despite increasing calls for stricter enforcement, shadow fleet vessels remain difficult to monitor. Sanctioned tankers deploy a number of strategies to evade detection – including flying under false flags, turning off their tracking signals, and broadcasting false locations.

“Once ships start making these direct port calls inside Russia, they will be less afraid to comply,” Zhminko told BBC Verify.

“Since it’s been allowed it’s easier for him to be part of the open shadow fleet – he can’t make any market port calls because he’s been allowed.”

According to the Center for Strategic and International Studies (CSIS), the shadow fleet tankers move between $87bn-$100bn worth of oil annually. Vaibhav Raghunandan, an analyst at the Center for Research on Energy and Clean Air, says that 68% of all Russian crude oil will be transported by sanctioned tankers by December 2025.

Mike Martin MP said the income generated by the shadow fleet helped fund Russia’s war in Ukraine and gave the Kremlin an economic lifeline. He said the conflict would only end “when the Russian economy collapses”.

“A key lever we need to pull is to knock out the sale of oil through the shadow fleet,” Martin told BBC Verify. “So I think it’s really important, it’s frustrating that we didn’t get it sooner.”

Additional reporting by Matt Murphy, Jack Fenwick and Joshua Cheetham.

Correction: The General Skobelev is the name of the authorized Russian tanker in the Channel, not the warship escorting it.