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 said: "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."
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The UK is dependent on its undersea cables and pipelines for its data and energy.
There are around 60 undersea cables which come ashore at several points along the UK coastline, particularly around East Anglia and South West England.
More than 90% of the UK's day-to-day internet traffic travels via these undersea cables.
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