UK Reveals Russian Submarine Operation

Declassified image of surface and sub-surface GUGI-associated vessels based at Olenya Guba base in Russia | Image: UK Ministry of Defence

The United Kingdom has disclosed details of a Russian submarine operation in waters near the UK, involving coordinated monitoring by British and allied forces in the High North and around critical undersea infrastructure.

According to the Ministry of Defence, a Russian attack submarine entered international waters several weeks ago and was tracked continuously by British aircraft and naval units. The submarine’s presence was assessed as part of a wider operation, acting as a diversion while other Russian vessels conducted activity elsewhere.

The UK worked with allies, including Norway, to identify and monitor vessels linked to Russia’s Main Directorate of Deep Sea Research (GUGI). These units are associated with operations involving subsea infrastructure such as fibre optic cables, which carry more than 99% of global data traffic, including communications, financial transactions and internet services.

British forces responded with a coordinated operation involving the Royal Navy and the Royal Air Force. Assets deployed included the Type 23 frigate HMS St Albans, RFA Tidespring and Merlin helicopters. RAF P-8 maritime patrol aircraft supported the operation, enabling continuous tracking of the submarine and associated vessels.

Sonobuoys were deployed to detect and monitor underwater movements, while naval vessels and aircraft maintained round-the-clock surveillance. The Ministry said the operation covered thousands of miles and was conducted alongside allied forces.

The UK and its partners also took steps to signal that Russian units had been detected. According to the Ministry, these actions ensured that the operation was no longer covert. The Russian submarine and GUGI-linked vessels later withdrew without completing their activity in secrecy.

British Prime Minister Keir Starmer said, “I am determined to protect the British people from paying the price for Putin’s aggression in their household bills. That is why we will not shy away from taking action and exposing Russia’s destabilising activity that seeks to test our resolve. Our Armed Forces are among the best in the world, and the British public should be in no doubt that this government will do whatever it takes to defend our national and economic security, wherever in the world that is needed.”

Defence Secretary John Healey said, “I want to pay tribute to the UK personnel who spent many days tracking these Russian submarines in extremely challenging and treacherous conditions. While the eyes of many – understandably – were on the Middle East, our British Armed Forces were simultaneously responding to rising Russian threats north of the UK. As we act to defend our interests and Allies in the Middle East, we are tackling increasing threats to NATO in the High North, maintaining strong support for Ukraine and protecting our UK homeland. To Putin, I say this: we see you, we see your activity over our underwater infrastructure. You should know that any attempt to damage it will not be tolerated and would have serious consequences.”

The Ministry highlighted that subsea fibre optic cables are central to global communications infrastructure. Disruption to these systems could affect banking, trade and communications networks.

The operation took place amid increased Russian naval activity near UK waters. Over the past two years, the UK has reported a rise in Russian vessels operating in the region. Previous incidents included the monitoring of the Russian vessel Yantar near UK waters, during which British aircraft were subjected to laser activity.

In a separate operation, the Royal Navy recently tracked multiple Russian vessels, including a destroyer, frigate, landing ship and a Kilo-class submarine, in the English Channel and North Sea. HMS Somerset and HMS Mersey, supported by RFA Tideforce and Wildcat helicopters, conducted the monitoring.

The UK said it is maintaining naval and air assets at readiness and continuing to work with allies to monitor and respond to activity near critical undersea infrastructure. Additional funding has been allocated to support P-8 maritime patrol aircraft and submarine tracking operations as part of broader efforts to strengthen maritime security.