Portsmouth-based patrol ship HMS Mersey kept a close eye on the surfaced RFS Rostov Na Donu during its voyage from the Baltic to the Mediterranean.
Pictures show the crew watching the diesel-powered Kilo-class attack sub from the gun deck while sailing alongside.
A Royal Navy spokesman said: “Mersey reported on the movements of the Russian Black Sea Fleet submarine so that Nato allies could track her progress as she continued her onward journey.”
The commanding officer of HMS Mersey, Lieutenant Commander Will Edwards-Bannon, said: “All of us in Mersey are very proud of the part we play, here in our home waters, in fulfilling the Royal Navy’s role of protecting our nation’s interests.
“No patrol is ever the same as the last and we have conducted a particularly varied range of missions recently, culminating with the tracking of this Russian submarine as it passes the UK.”
Mersey was also on duty when the Rostov Na Donu made the reverse voyage in October last year.
It was tracked while returning from operations in the Mediterranean, where Russian forces have been engaged in action in Syria.
Kilo-class subs, in service since 1980, are designed to sink ships and other subs with their 18 onboard torpedoes.
Some are also armed with land-attack cruise missiles, anti-ship missiles, and mines.
It is the latest hostile show by Putin’s forces, which routinely test British and US defences with close approaches.
RAF jets are scrambled several times a year to intercept nuclear bombers nearing UK air space.
In November, two Russian warships including a spy vessel bristling with eavesdropping tech were detected lurking near the Moray Firth, Scotland.
The Navy confirmed it had intercepted the vessels during a mission which fell under “Defence Task One” – launched to protect the territorial integrity of Britain.
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