Russian attack submarines have conducted missions around the Irish Sea twice since the 2022 invasion of Ukraine, this according to Bloomberg News.
The first deployment of a Russian Kilo-class submarine close to the Irish Sea, happened around 18 months ago while the second occurrence took place more recently, the report stated.
Though the sea be named Irish its international waters would come under the purview of NATO.
The extent of the submarine movements went beyond what British officials had previously seen, the Bloomberg News report said.
U.S. officials were aware of the sub movements, the report added.
Reuters reported that Russia's and Ireland's defense ministries, Britain's foreign ministry, and the White House did not immediately respond to a request from the news agency for comment.
The Kilo-class submarine is a diesel-electric attack submarine capable of firing Russia's cruise missiles, as well as torpedoes and naval mines.
British nuclear submarines regularly cruise in the Irish Sea to and from their base in Scotland.
The seas and air around Ireland have seen considerable Russian activity in recent years. Russian bombers have flown down Ireland's west coast, at times with their transponders switched off, a hazardous action in the context of civil air routes.
Back in 2022 a Russian live fire naval exercise in the Irish Maritime Exclusive Economic Zone was moved westward after protests from Irish fishermen who put to sea in a protest flotilla. They pointed out that the exercises were set to take place in rich fishing grounds.
They were also planned in an era of the Atlantic where many transatlantic undersea cables converge and this raised serious concerns in western capitals.
Concerns have been expressed since that incident that Russian ships have been mapping seabeds off Ireland.
