The Irish Aviation Authority has confirmed that two Russian military aircraft flew within Irish-controlled airspace yesterday.
In a statement the IAA said the aircraft operated within 25 nautical miles of the Irish coast.
But it said the aircraft did not enter Irish sovereign airspace at any time.
It said the flight posed no safety threat to civil aviation on this occasion.
The IAA confirmed it monitored the activity of two Russian military aircraft off the west-south/ east coast of Ireland for about four hours yesterday from about 3-7pm.
The authority said it was not informed in advance.
It comes as the British Ministry of Defence said that RAF jets were scrambled yesterday after two Russian military aircraft were seen off the Cornwall coast.
The Russian Bear bombers were escorted from the UK area of interest, but did not enter its sovereign airspace.
The IAA said the aircraft operated in North Atlantic airspace and in airspace under the control of the IAA.
Irish controlled airspace extends 256 nautical miles off the west coast of Ireland. Irish sovereign airspace extends 12 nautical miles off the Irish coast.
Last month, the Irish Aviation Authority confirmed that two Russian military aircraft, shadowed by a number of British fighter jets, flew through Irish controlled airspace off the west coast.