REUTERS
The French navy detected a Russian submarine carrying nuclear missiles in the Bay of Biscay in January, according to Reuters citing a Thursday report by Obs magazine.
According to Obs referring to a senior French official, the submarine, from the Murmansk base, did not enter France's territorial waters, but was seen off France's Atlantic coast.
A spokesman for the French navy neither confirmed or denied the information saying it was a general policy not to communicate on such matters, Reuters wrote.
"Russian naval activity has been on the rise for several months, if not years, and we are permanently attentive to it," the spokesman said.
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In Britain and Sweden patrol planes have searched their waters over the past two years after the sighting of a submarine's periscope and reports of foreign "underwater activity".
In mid-February French and British fighter jets scrambled two Russian Tu-160 bomber planes heading towards British airspace near the French coast.