The United Kingdom is escalating its crackdown on Russia’s covert oil transport network, granting military and law enforcement teams new powers to intercept sanctioned vessels passing

through British waters.

Under the new directive approved by Prime Minister Keir Starmer, UK forces can now board and detain ships linked to Moscow’s so-called “shadow fleet” — a sprawling network of aging tankers used to bypass international sanctions and sustain Russia’s war economy.

The move marks a significant intensification of Western efforts to disrupt the financial arteries supporting President Vladimir Putin’s war in Ukraine. It comes as Starmer meets with northern European allies at the Joint Expeditionary Force Summit in Helsinki, where regional security and maritime enforcement are high on the agenda.

In recent weeks, the Royal Navy has already played a key role in tracking suspect vessels, supporting allied operations across European and Mediterranean waters. Several partner nations — including Finland, Sweden, and Estonia — have stepped up their own interdiction efforts in the Baltic Sea, targeting ships believed to be operating outside international law.

By extending enforcement into UK waters, including critical routes such as the English Channel, British authorities aim to choke off access to key maritime corridors. Officials say the strategy will leave operators with stark choices: reroute via longer and more expensive paths, or risk detention and legal action.

Prime Minister Keir Starmer said: “We are living in an increasingly volatile and dangerous world, facing threats from different fronts across the world every day. As Prime Minister, my first duty is to keep this country safe and protect British interests here and abroad. Putin is rubbing his hands at the war in the Middle East because he thinks higher oil prices will let him line his pockets. That’s why we’re going after his shadow fleet even harder, not just keeping Britain safe but starving Putin’s war machine of the dirty profits that fund his barbaric campaign in Ukraine.
He and his cronies should be in no doubt, we will always defend our sovereignty and stand with Ukraine for as long as it takes”.

Security concerns are particularly acute in the Arctic and High North, regions seen as vital to Britain’s economic and strategic interests. With Russia’s Northern Fleet capable of threatening key infrastructure — from energy supplies to undersea data cables — officials warn that maritime security is now inseparable from national resilience.

The UK has spent years monitoring the shadow fleet and recently supported a US-led seizure of the tanker *Bella 1*, a case that helped shape the current policy shift. Since then, British forces have been preparing for complex boarding scenarios, including encounters with non-compliant or technologically sophisticated vessels attempting to evade capture.

Each interdiction operation will be assessed individually, with input from military, legal, and energy experts before ministers give final approval. Ships found in breach of sanctions could face detention, with potential criminal proceedings against owners, operators, and crew.

The scale of the challenge is significant. An estimated 75% of Russia’s crude oil exports are transported via this shadow network. In response, the UK and its allies have already sanctioned more than 500 vessels linked to the operation.

British officials are now calling for deeper coordination among Joint Expeditionary Force partners to expand enforcement efforts, signaling a long-term commitment to curbing Russia’s maritime sanctions evasion — and tightening the economic pressure on the Kremlin.