During a press conference yesterday, UK Defence Secretary John Healey exposed that Russia has ‘increased activity’ in the Atlantic Ocean.

He explained that, as part of a month-long military operation conducted by the UK, three Russian submarines carried out a covert operation above subsea cables and pipelines to the North of the UK for longer than one month.

While he said there is “no evidence” that any infrastructure was damaged, Healey explained that UK warships and aircraft were monitoring the Russian vessels 24/7. During a press conference yesterday, he highlighted how, while vessels like this survey underwater infrastructure during peacetime, they have the potential to “sabotage” it during times of conflict.

“We see you,” Healey said to Putin directly during a press conference yesterday. “We see your activity over our cables and our pipelines – and you should know that any attempt to damage them will not be tolerated and have serious consequences.”

Roughly 60 cables connect the UK to the global network. Being an island, the nation is very dependent on undersea cables and pipelines for data and energy, with most of its daily internet traffic travelling through these essential cables.

“Half of the gas that heats our homes. 99% of international telecoms and data traffic. Trillions of pounds of global trade each day,” Healey explained in his speech. “For all the reasons the seabed matters so much to us, are the reasons that make it the prime target for our adversaries.”

If damaged, the UK could be left vulnerable. Consequences of damaged subsea cables can include disruption to international internet traffic, an inability to complete financial transactions, or even threats to energy supplies.

“These aren’t standard submarines, they’re specialist vessels designed for deep sea operations,” Charlotte Wilson, head of enterprise at Check Point Cybersecurity, said of the Russian vessels, as reported by the BBC.

She added: “[This incident] suggests a deliberate effort to understand where critical infrastructure sits and how it behaves. Not only mapping locations but also assessing how resilient those systems are.”

The news comes after several high-profile attacks on subsea cables and pipelines – including a suspected attack in the Baltics in 2024 and an attack on the Nord Stream 1 and Nord Stream 2 gas pipelines in 2022.

While the UK’s undersea network is resilient, increasing threats worldwide have led the government to provide additional support to counter such incidents.

“We’ve launched the Atlantic Bastion programme to combine the latest autonomous technologies with the very best warships and aircraft to create a British-built hybrid naval force,” Healey explained during his press conference. “We’re making the biggest sustained increase in defence spending since the end of the Cold War.”

This investment has taken place during ongoing conflict in the Middle East and after damage to cables in the Red Sea in September 2025, which caused widespread disruption. While that particular incident involved no military conflict, it perhaps acted as a warning of what subsea attacks could look like.

In Capacity’s recent subsea sector report, executives warned that connectivity risk is now about understanding the physical impact of your network infrastructure, including which geopolitical environments cable routes pass through.

Perhaps, as Healey said yesterday, silent and unseen threats really are the worst of all.

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