Russian submarine activity in the North Atlantic: Why undersea infrastructure protection has never been more critical
Published 10th April 2026
The statement by Defence Secretary John Healey confirming a month-long covert Russian submarine operation north of Britain will come as little surprise to those of us working in defence technology, but it is no less serious for that.
Three Russian submarines, including an Akula-class attack submarine and two specialist deep-sea research vessels from GUGI, Russia's Main Directorate for Deep-Sea Research, were tracked operating above undersea cables and pipelines in the North Atlantic for more than a month. The intelligence gathered by these vessels is designed to help Russia survey critical infrastructure during peacetime and sabotage it in times of conflict. We welcome the Government's swift and decisive response and the transparency shown in calling out this activity publicly.
The stakes for critical undersea infrastructure
Britain is an island nation and connection is everything, for our economy and our security. Beneath our waters lies a vast network of cables and pipelines on which our way of life depends. Half of the gas that heats our homes and 99% of international telecoms and data traffic. Any disruption to this infrastructure would not be a technical inconvenience. It would have immediate and far-reaching consequences for financial markets, communications, energy supply and national security.
The Defence Secretary confirmed that Britain has seen a 30% increase in Russian incursions threatening UK waters and this latest episode is a stark reminder that the threat to undersea infrastructure is persistent, evolving and highly sophisticated. The use of specialist deep-sea research submarines, capable of mapping and accessing cable routes in detail, represents a qualitative step up from surface-level surveillance activity.
Technology as the critical differentiator
Detecting and deterring this kind of threat demands advanced, persistent and autonomous capability. This is precisely where Cohort business technologies are playing a growing role.
KraitSense, our business SEA’s acoustic sensor system, delivers real-time detection and classification of underwater threats, giving operators the awareness they need to act decisively and early. Designed for use with UUVs (uncrewed underwater vessels) it provides persistent surveillance without putting personnel at risk. Our business ELAC SONAR’s ENLITOR and ERAZOR technology detects and disrupts threats to underwater infrastructure, providing a practical and deployable solution to this clear and urgent threat.
The Government has launched the Atlantic Bastion programme to combine the latest autonomous technologies with crewed platforms in defence of the North Atlantic. The technologies being developed and deployed across Cohort are directly aligned with this programme's objectives, and with the broader ambition to build effective capability for the defence of UK and allied waters.
Protecting the UK and its allies
Across the Cohort Group, our companies are working at the frontier of undersea defence technology, from autonomous systems and acoustic sensing to data fusion and maritime intelligence. This is not a future capability. It is being delivered now, in support of the Royal Navy and allied partners who are on watch every day to protect the infrastructure that underpins modern life.
This news is a reminder of why that work matters, and why investment in this domain cannot wait.
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