Russia on Monday denied a report that one of its submarines was suffering technical problems after the vessel surfaced off the coast of northern France.
NATO's Maritime Command published photographs on October 9 of what it said was a French Navy frigate observing a Russian submarine operating on the surface off the coast of Brittany.
"NATO stands ready to defend our Alliance with constant vigilance and maritime awareness across the Atlantic," it posted on social media, without naming the submarine.
VChK-OGPU, a shadowy social media channel that publishes purported Russian security leaks, reported last month that the diesel-powered submarine Novorossiysk was suffering serious technical problems, with fuel leaking into the hold.
On Monday, state media published a statement from Russia's Black Sea Fleet denying that the Novorossiysk had surfaced off France because of a technical emergency.
It said that the submarine was carrying out a scheduled transit after completing tasks in the Mediterranean Sea, and had surfaced in line with international navigation rules in the English Channel.
State news agency TASS said the vessel, which entered service in 2014, was part of a group of submarines that carry Kalibr cruise missiles.
(Reporting by Reuters; writing by Mark Trevelyan)
