Commuters could be facing a summer of disruption after workers at Irish Rail walked out on talks over the cost-saving plan at the company.
The 500 members of the National Bus and Rail Union (NBRU) will now be balloted for a strike mandate if Irish Rail goes ahead with unilateral cuts to pay and conditions.
If the ballot is passed, strike notice of at least a week would need to be served.
SIPTU members at Irish Rail voted for industrial action if management presses ahead with the plans by a ratio of 2-to-1.
The union says it would call a one-day work stoppage.
SIPTU members also recently voted by 51% to 49% against a Labour Court recommendation which involved pay cuts, redundancies and restructuring at the company.
The company wants to change workers' terms and conditions in a bid to save €8.7 million this year.
According to SIPTU Organiser, Paul Cullen, industrial action will only occur if management "acts provocatively" by changing members' conditions of employment without agreement.
The Irish Times industry correspondent Martin Wall told Newstalk Breakfast that the company is still determined to make the cuts - and that spells trouble for commuters.
