Revision History

The UK revealed on April 9, 2026, that it tracked three Russian submarines — including two GUGI deep-sea espionage vessels — for over a month as they operated near critical undersea cables and pipelines in the North Atlantic. Defence Secretary John Healey warned Putin of "serious consequences," while Russia denied threatening any infrastructure, raising questions about the legal framework governing submarine activity in international waters and the adequacy of NATO's post-Nord Stream seabed defences.