Three Russian submarines conducted a covert operation over cables and pipelines in waters north of the UK, Defence Secretary John Healey said.
A British warship and aircraft were deployed to deter the malign activity by Moscow, and there was no evidence of any damage to UK infrastructure in the Atlantic, he added.
Addressing Russian President Vladimir Putin directly, Healey stated, We see you. 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 will have serious consequences.
The Russian embassy in London has denied Healey's claims, asserting that Russia is not threatening underwater infrastructure critical to the UK.
The UK heavily relies on its undersea cables and pipelines for data and energy, with around 60 undersea cables coming ashore at various points along the UK coastline.
More than 90% of the UK's day-to-day internet traffic travels via these undersea cables.
Healey claimed Russia sent an Akula-class submarine as a diversion while two of its GUGI spy submarines conducted surveillance of these cables.
Our armed forces left [Russia] in no doubt that they were being monitored, that their movements were not covert, as President Putin planned, and that their attempted secret operation had been exposed, he stated.
Britain and NATO's concern is that Russian covert surveillance of Western undersea cables and pipelines could give Moscow an advantage should hostilities erupt. The UK's Secretary of Defence remains vigilant, asserting the country's capability to track and monitor future Russian activities.
