More than 150 railway workers in Northern Ireland are to go on strike over pay and conditions, it has been revealed.
Conductors, station and platform staff will take part in industrial action beginning at midnight on Monday and lasting a day, the GMB union said, after refusing to agree to cost-saving measures like changes to sick pay.
A spokeswoman for train operator Translink said the organisation was working hard to resolve the matter.
Michael Mulholland, GMB regional organiser, said: "GMB members in Translink on Northern Ireland Railways have voted to take part in action, up to and including strike action."
He added: "GMB members, who are mainly from the conductor and station staff grades, believe that they are being asked to give away too much to fund increases for other groups who have not."
The union said its members were responsible for revenue protection, train and passenger safety but claimed there was a history of poor industrial relations. It added the action related to an ongoing dispute with publicly-funded employer Translink over pay and terms and conditions.
The 24 hour stoppage will begin at midnight on Monday. Mr Mulholland said all other unions had accepted a three-year deal through the agreement of efficiencies like changes to company sick pay and increased flexibility. GMB members believed they were being asked to give away too much.
A Translink spokeswoman said: "A small number of railways staff have indicated they will take strike action on Monday 24th June. We are working hard to resolve this with the trade union involved.
"Rail services will be affected by this strike action and we will keep our passengers informed as more information becomes available."
Bus services will not be affected.