British Defence Secretary John Healey told parliament Wednesday the Royal Navy was tracking a "Russian spy ship" that passed through UK waters, warning Russia's President Vladimir Putin: "We know what you're doing".

The nuclear-powered hunter-killer submarine surfaced close to the Yantar to let the Russian ship know it was being watched.

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

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’

A Royal Navy attack submarine surfaced close to a Russian spy ship off the UK coast in an extraordinary warning to stop spying on British undersea cables, the defence secretary has revealed.

Returning to the Defence Secretary’s statement to Parliament earlier, John Healey said the UN “law of the open seas” means there are options “not available” to the Government in limiting foreign vessels in UK waters. It comes after Healey revealed that a Royal Navy submarine was used to warn off one of Vladimir Putin’s spy ships.

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

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.

A Royal Navy submarine was authorized to surface close to a Russian ship "strictly as a deterrent measure," British Defense Secretary John Healey said.