Travel plans for thousands of commuters could be thrown into chaos when railway staff in Northern Ireland stage a 24-hour strike over pay and conditions.
Conductors, station and platform staff will take part in industrial action beginning at midnight on Sunday, the GMB union said, after refusing to agree to cost-saving measures such as changes to sick pay.
The union said the action, involving 150 members, related to an ongoing dispute over pay and terms and conditions "as well as a history of poor industrial relations".
Last year a decision to award train drivers a huge pay rise of 18% over three years sparked controversy and public outrage.
But despite speculation to the contrary, GMB regional organiser Michael Mulholland said its members are not striking to obtain a similar hike.
Translink is aware of the planned strike and a spokeswoman said the company is working hard to resolve the situation.
She said: "Rail services will be affected by this strike action and we will keep our passengers informed. Bus services will not be impacted."
There are fears the strike action will cause major chaos and lead to loss of revenue for Translink, with managers expected to take up operational posts.
Mr Mulholland told the Belfast Telegraph that the dispute was not about money, adding the 6.25% they had been offered was "perfectly acceptable in the current economic climate".
"All other groups have accepted a three-year deal, which has been achieved through the agreement of efficiencies such as changes to company sick pay and increased flexibility," he said.
"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.
"We don't want an 18% pay increase because the train drivers had to renegotiate a complete contract to achieve whatever they achieved, and there's a reduction in the number of train drivers as part of that as well," he said.
"What we want is a fair and equitable increase for our members and for our members not to be treated less favourably than any other group.
"It has to do with efficiencies more than anything else – we're talking about fewer people to do more work because there has been a reduction in headcount over a number of years."
Mr Mulholland said further strike action could not be ruled out. Meanwhile, the trade union Siptu, which has 205 members, has agreed to the deal.
Once again Translink is in the news for all the wrong reasons. In April we revealed that taxpayers ploughed almost £130m into Translink in the last financial year. Consumers also saw fares on buses, trains and coaches rise up to 8% on some services. Last month it emerged that plummeting passenger numbers were causing fears for the viability of the Dublin to Belfast rail service.