On 17 September 2025, Sky News reported that Russian intelligence vessels and unmanned underwater vehicles have been actively collecting data on European undersea cables and pipelines. Analysts warn that in the event of a potential Russian attack, the United Kingdom could lose communication links and access to critical resources. According to the International Institute for Strategic Studies (IISS), around 95% of global internet traffic and up to $10 trillion in daily financial transactions flow through these cables. From the UK coastline alone, about 60 undersea cable systems are connected, and repairs in deep waters require advanced technology.
Intelligence gathering and rising risks
Experts note that Russia has been covertly mapping Western undersea networks for years, including restricted military sites. Defence Secretary John Healey confirmed that the Russian research vessel Yantar is used by Russian intelligence to collect information on the UK’s subsea infrastructure. In addition, increased activity of Russian underwater drones has been recorded near these lines. As Sky News highlighted, Moscow now possesses a detailed map of Britain’s undersea cable network, creating a potential vulnerability for targeted attacks. While accidental damage often results from fishing or commercial activity, deliberate disruption would pose a far greater strategic threat.
Historical parallels and modern capabilities
Collecting information on undersea infrastructure is not a new practice. During the Cold War, the Soviet Union conducted similar operations, including the covert installation of listening devices on submarine cables. Today, the scale is unprecedented: autonomous underwater vehicles enable wider coverage, making monitoring more complex and expanding the potential range of attacks. Russia’s naval intelligence units, including the GRU’s naval special forces and the Main Directorate for Deep-Sea Research, are capable of hybrid maritime operations. Beyond the Yantar, the Russian navy operates a fleet of specialised research and support vessels, many of which can deploy underwater drones.
Hybrid warfare and testing of Western resilience
Analysts describe cable damage as part of Russia’s hybrid warfare strategy against the West. By operating in a “grey zone” short of open aggression, Moscow probes the ability of Western states to identify and prove responsibility for sabotage. These operations also serve as tests of resilience: how quickly European and US companies can reroute traffic and repair damaged cables. Disruptions to energy and telecommunications networks could cause chaos in government, defence, financial systems and international payments. Experts warn that the growing number of incidents shows Western allies remain ill-prepared to protect undersea communications.
Political and security responses
In response to the risks, the UK Parliament earlier this year launched an inquiry into the state and security of subsea communications. Committee chairman Matt Western stressed there is no need to panic but emphasised the need for awareness, warning that such an attack would be a serious blow. Meanwhile, Finland is investigating the case of the Eagle S tanker, suspected of damaging Baltic Sea cables in December 2024. A trial against the captain and two crew members began in August 2025, with charges relating to the destruction of five cables. These developments underline the vulnerability of critical infrastructure and highlight the challenge NATO faces: undersea incidents may not qualify as direct armed attacks, complicating the application of Article 5 of the Washington Treaty.
