Workers at Iarnród Éireann are to strike on five separate days in August and September over plans to impose pay cuts.
The rail company said it it will not be in a position to operate any services on Sunday 24 August, Monday 25 August, Sunday 7 September, Monday 8 September and Sunday 21 September due to action by members of SIPTU and the National Bus and Rail Union.
SIPTU had originally proposed a work-to-rule and has now issued the company with notice of full work stoppages.
Iarnród Éireann formally advised the trade unions and employees that the company will implement measures to achieve payroll savings across its workforce from Sunday 24 August.
The proposals had been accepted by members of TSSA, TEEU and Unite trade unions but were rejected by SIPTU and the NBRU.