Transport Minister Shane Ross has insisted that he won't intervene in the Irish Rail row - despite the prospect of extra strikes in the run-up to Christmas.
It has emerged that union chiefs are threatening to ramp up industrial action over pay ahead of the festive season.
Two further 48-hour strikes are being considered on the weekends before Christmas - including on December 23 and Christmas Eve - unless staff are offered the same pay rate as bus and Luas drivers.
Around 155,000 commuters around the country were affected by the one-day strike on Wednesday, which brought all rail services including Dart and Intercity routes to a halt.
Business groups have raised fears of the potential economic impact if industrial action is expanded in the build-up to Christmas.
However, Mr Ross has stuck to the Government's position that it won't get involved in the row.
Instead he said the State's industrial relations mechanisms were the appropriate forum to resolve the dispute between Irish Rail management and unions.
"I sincerely hope that won't happen," the minister said, responding to the threat of additional industrial action ahead of the festive season.
"I very much urge both sides, the management and unions, to go back to the WRC [Workplace Relations Commission] and the Labour Court as soon as possible. I will not be intervening."
The four remaining one-day strikes already planned - including the second strike next Tuesday - are set to go ahead as workers seek a 3.75pc pay rise.
Irish Rail has offered employees a 1.7pc increase, which the National Bus and Rail Union (NBRU) and Siptu have described as "miserly".
Separately NBRU general secretary Dermot O'Leary dismissed Taoiseach Leo Varadkar's suggestion of restricting the right to strike by workers in essential services as "populist bluster".
Mr Varadkar made the proposal during his Fine Gael leadership campaign.
Commenting on the Irish Rail dispute during his trip to the United States, the Taoiseach said his promise to restrict strikes in essential services could become party policy ahead of the next election.
"Workers will find an alternative way to protest," Mr O'Leary said, if such moves were implemented by a future government.
Mr Varadkar was also critical of the current industrial action by rail workers, saying they would end up with a deal that "will probably be no different than if there'd been no strike at all".
Mr O'Leary said the Taoiseach was showing "ignorance of industrial relations" with his comments.