RUSSIAN ships were monitored by the Republic's Defence Forces after they entered Irish waters in recent days.
Four vessels entered Ireland's exclusive economic zone (EEZ), sparking concerns that they were close to undersea cables.
The Republic's Defence Forces said it and the British Royal Navy monitored the ships "during the conduct of air and naval patrols", adding they had departed the Irish EEZ.
It has been speculated the ships' presence is related to a refuelling mission, as Russian vessels are not allowed to dock in any EU or British ports.
Defence minister and Tánaiste, Micheál Martin, said he did not believe the vessels presented a threat, but added: "It's something we are very conscious of and we keep a very close eye on".
Speaking to the Newstalk radio station, security expert Declan Power said the ships appearing to "loiter in the area" prompted concern over the cables.
He added that the Republic's Defence Forces were “extremely lucky” to be able to monitor the vessels, as the cables "are responsible for a huge amount of commercial and other traffic between the United States and Europe".
“Damage to them would interfere with internet traffic of a personal nature, of a national nature, international nature and international commercial nature," he said.
“The other aspect of this is that it is known, since the war in Ukraine, the Russians have been targeting and mapping external information of that nature - undersea cables, wind farms - anything of that nature that would be difficult to protect.”
Mr Power said Russia was seeking "weak points" in Europe's security, with Ireland likely seen as a "wobble spot".
In 2020, Russian bombers were spotted in Irish-controlled airspace, with commercial and private flights over the Atlantic warned about their presence.
Their appearance prompted Britain's RAF to scramble jets to monitor the bombers while they were in "the UK area of interest”.
