LONDON, August 4. /TASS/. New Russian submarines Varshavyanka or Project 636, known as Kilo-Class submarines, are feared to be operating in the British territorial waters unseen and unheard by the Royal Navy, The Telegraph said on Sunday citing senior military sources.

According to the daily, new Russian submarines equipped with low-noise diesel engines allegedly pose a threat to British security by tracking Britain’s fleet, tapping undersea cables and eavesdropping on telecommunication systems.

"The new First Sea Lord needs to deliver the underwater battle," the source told The Telegraph. "We must be better at what we do."

"The Russians are benefiting from a huge increase in research and development spending 15 to 20 years ago which is now producing this new class of super-quiet Kilo Submarines," he added.

The Telegraph cites Admiral Tony Radakin, the new head of the Royal Navy, who said in his first public statement as head of the navy about a greater risk of state-on-state conflicts in the world and pledged to invest more in the North Atlantic "to maintain the freedom of maneuver of the nuclear deterrent."

Russia’s embassy in London has reiterated that British politicians and military figures were frightening the British people with an alleged Russian threat seeking a boost in defense funding.