Rishi Sunak was given a “secret briefing” after a Russian nuclear submarine was spotted off the coast of Scotland, it has been revealed.
The Prime Minister and Defence Secretary Grant Shapps were alerted to the detection of President Vladimir Putin’s Yasen-class vessel earlier this month.
An RAF surveillance plane tracked the submarine's movements along the west coast of Ireland to Scotland.
The Sunday Express reported the 13,800-tonne submarine Kazan passed by the UK’s nuclear naval base in Faslane without crossing into British waters, prompting swift reports back to the Permanent Joint Headquarters in Northwood, north west London.
Kazan was picked up by an RAF Poseidon P8 anti-submarine aircraft on June 5 which dropped sonar buoys used to detect subsurface activity.
Kazan was expected to head on to Venezuela and Guyana, where Royal Navy patrol ship HMS Trent had recently deployed.
Military commanders were reportedly concerned that the vessel could be looking for vulnerabilities around the UK.
A Royal Navy spokesman said: “The Royal Navy routinely monitors UK territorial waters and the adjacent sea areas to ensure compliance with maritime law, to deter malign activity and to protect our national interests.”
Dmitry Peskov, a Kremlin spokesman, said there was no reason to worry, adding: “This is a normal practice for all states, including such a large maritime power as Russia. So we don't see any reason to worry in this case.”
Kazan, half submerged with its crew on deck, and the Admiral Gorshkov frigate sailed into Havana harbour on Wednesday after conducting high-precision missile weapons training in the Atlantic.
Cuba’s foreign ministry said the vessels carried no nuclear weapons, an assertion repeated by US officials.
Russian pro-war Telegram channels boasted that Kazan has “guided missile weapons” on board as it passes close to the American coastline, around 25 miles east of Florida.
Russia's defence ministry said in a statement the drills involve hitting targets from a distance of more than 370 miles and following an exercise in anti-aircraft fire.
Both the Admiral Gorshkov and the Kazan are usually key vessels in Putin’s nuclear strike force.
