UK updates on Russian submarine activity targeting undersea infrastructure

The United Kingdom (on behalf of Norway and the Netherlands) announced an update on Russian undersea activity in the North Atlantic.

• Announcement: The UK tabled an update to the Council relaying the UK Defence Secretary’s 9 April 2026 briefing; the reported operation involved a Russian Akula Class Submarine and two GUGI specialised submarines (including the spy ship YANTAR) operating across the North Atlantic and within UK and Allied Exclusive Economic Zones. The UK, with Norway and other Allies, tracked these vessels 24/7 using a Royal Navy warship and RAF P8 aircraft; the operation lasted more than a month and has now concluded.
• Background/details: The GUGI vessels (Main Directorate for Deep-Sea Research) are described as conducting hybrid warfare targeting Critical Undersea Infrastructure — surveying in peacetime and prepared to sabotage in conflict. The Akula returned home after being closely tracked; the two GUGI submarines have also returned home. The UK emphasized transparency, risk reduction, and readiness to respond; Norway and the Netherlands aligned with the statement.