The United Kingdom has confirmed that one of its Royal Navy nuclear-powered submarines surfaced close to the Yantar, a notorious Russian spy ship late last year, to make it clear it was being observed.

In a message to Vladimir Putin, Defence Secretary John Healey said ‘we see you, we know what you are doing and we will not shy away from robust action to protect this country’

The UK authorized the British submarine to surface closely to the Russian vessel to warn it off, British defense secretary Healey said.

Defence Secretary John Healey said Russia "remains the most pressing and immediate threat to Britain", and added that "any threat will be met with strength and resolve".

John Healey warned Vladimir Putin ‘we see you, we know what you are doing and we will not shy away from robust action’.

Royal Navy submarine used to warn off Russian spy ship loitering over cables - The nuclear-powered hunter-killer submarine surfaced close to the Yantar to let the Russian ship know it was being watched.

Last November, a British submarine surfaced close to the Russian spy ship Yantar to warn it had been covertly tracked while operating near critical underwater infrastructure.

Moscow’s intelligence ship Yantar enters UK waters in ‘another example of growing Russian aggression’, according to the Defence Secretary

Britain said it monitored a Russian spy ship in the English Channel in recent days and would strengthen its response to secret operations by Russian ships and aircraft in an effort to protect undersea cables.

The British Navy detected a Russian spy ship in the English Channel this week. This vessel had previously been observed near critical underwater infrastructure in British waters. The spy ship was tracked a few weeks after it was first seen over crucial underwater infrastructure in British waters.

A British official sent a public warning to Russian President Vladimir Putin on Wednesday after the Royal Navy started tracking the Russian spy vessel Yantar in British waters this week.