Unions at Bus Éireann have said to prepare for strike action from next week.
The board of the company announced their cost-cutting plans within the past hour and confirmed that immediate cost savings would be implemented from Monday.
They said that the measures are vital to ensure the company can continue to trade as a going concern.
“Due to the perilous state of the company's finances and the failure to reach agreement with unions at the Workplace Relations Committee (WRC) last week, the Board of Bus Éireann considered the matter in detail at its meeting today and approved proposals for immediate cost savings to be implemented.”
Siptu's Willie Noone said they have left workers no other option but to take strike action to protect their livelihoods.
He said: "They’ve announced the changes and are implementing them. Apart from the fact that they have already implemented changes without any agreement, they are now going ahead and forcing in more changes.
“Our members have enough at this stage so it is time to stand up now and fight and they have indicated to us that they are quite clearly willing to do so.”
General Secretary of the National Bus and Rail Union, Dermot O'Leary, said: "Bus Éireann management are determined to steer a course towards conflict by issuing ultimatums to staff, before they have had the opportunity to digest, never mind analyse the detail contained in this latest missive.
Placing an emphasis on, as it were, parking the race to the bottom agenda for now, and replacing it with broad sweeping generalisations under insider-specific language, is obviously designed to create an impression that there has been a major shift in policy, away from raiding workers’ pay packets to plug the policy induced financial gap at Expressway.
"The fact is that by informing staff that they are going to introduce far reaching and financially impactful measures from next Monday, without agreement, Bus Éireann has left us with no option but to inform the company that we will reactivate our previously notified strike action to coincide with the implementation of these measures."
A spokesperson for Bus Eireann has said that the impending action will not affect school buses.
Before an Oireachtas committee last month, Ray Hernan, acting chief executive at the State bus company, said it lost between €8m and €9m last year, and had only €7m left in reserves.
Mr Hernan said Bus Eireann will be insolvent by the end of this year - on its 30th anniversary - with the loss of all 2,600 jobs unless an emergency survival plan is agreed.
He also indicated staffing costs other than basic pay, such as overtime shift allowances, rota allowances and lunch expenses, will come under the axe in a root and branch cost-cutting review expected in March.
Absenteeism, which is double the national average, will also have to be tackled, he told the hearing.
Mr Hernan said Bus Eireann's board of directors has until the end of March to sign off on last year's accounts but it would not be able to do so unless there is a drastic and decisive rescue plan in place before then.
Unions claim cost-cutting measures being proposed by the company will result in effective pay cuts of up to 30%.