BUS Eireann's boss has warned the company's 2,500 members of staff that they may have no jobs to go to if they do not accept €4.8m cuts to their premium pay, expenses and holidays.
Chief executive Martin Nolan told workers that industrial action could lead to widespread redundancies, as the company's future is in jeopardy.
He said Bus Eireann has "no safety net", unlike the wider public service, and it would have no option but to cut pay and reduce staff if they did not co-operate.
"If we do not reduce our cost base, job losses may be unavoidable," he said.
"Any industrial unrest that may potentially arise would only exacerbate the situation and, unlike those directly employed in the public and civil service that would have jobs to return to after any industrial action, we may not.
"Industrial action would see us lose business to our competitors overnight that may never be regained."
He said it was important that staff understood the precarious nature of the company's situation.
The semi-state transport boss said it had to achieve savings of €20m, but €7.6m payroll savings had yet to be delivered.
It said acceptance of Labour Court-backed cuts would deliver €4.8m savings.
He said the payroll cuts would impact on all staff, including management, who had to contribute over 8pc of the cuts.
The chief executive's letter was sent to workers after it emerged that unions SIPTU and TSSA have recommended a 'No' vote to a Labour Court ruling backing the cuts.