The National Bus and Rail Union (NBRU) has accused government and management in Iarnród Éireann of “playing Russian roulette” with transport policy.
Unions were responding to reports the company has said pay increases could not be given to staff given because of severe financial difficulties.
The company has said it has accumulated losses of €159m.
In a statement NBRU general secretary Dermot O’Leary suggested successive Governments had forced Iarnród Éireann “to preach the poor mouth to its own staff, who through two cost-cutting programmes ... have contributed to the success story that now has the Company reporting passenger numbers back at Celtic Tiger levels."
Mr O'Leary went on to suggest this is in direct contradiction with the so-called insolvency threat being peddled by Irish Rail management to workers.
"What we are actually witnessing here is a systematic attack on State-owned public transport Companies and workers.
"The recent Bus Éireann dispute clearly demonstrated that an agenda exists within Government circles, to drag the CIÉ Companies and their workforce through a series of industrial disputes in order to feed a pro-privatisation agenda
He concluded: "It is long since passed time that those who provide support for this government cried halt to this Russian roulette transport policy, before we are forced into a summer and autumn of chaos across our railways.”