Siptu has told its members in Bus Éireann today to prepare for protracted strike action.
The union has called on them to support a political campaign targeting rural TDs who they say are "propping up a government which is intent on destroying the public bus transport system in their own constituencies".
Siptu's Willie Noone said: "Following the decision of the management of Bus Éireann to cease discussions with the unions in the Workplace Relations Commission it became clear that an indefinite strike was probably unavoidable.
"The combination of the inertia shown by the Department of Transport, the National Transport Authority and the Minister of Transport, Shane Ross, along with the fact that TDs from rural areas who are propping up the Government have gone into hiding on this issue means that our members must prepare for a hard and protracted battle.
"Placards and other materials for the strike action have been sent from Liberty Hall in Dublin to the Siptu offices in Cork, Waterford, Tralee, Galway, Castlebar, Letterkenny, Drogheda and Sligo."
He said that all Siptu members in Bus Éireann will take part in pickets, with the exception of school bus drivers.
The union representative said: "They are not currently involved in the dispute and have yet to be balloted on strike or industrial action. However, this situation is under constant review.
"Siptu is not initiating this dispute and has been available for discussions with management for months. However, at no time has management presented union representatives with a plan which shows how it can continue with Expressway Services while shedding jobs, closing locations and making employees work less hours.
"Instead, it issued a letter on 18th January 2017 stating that it intends to implement a plan that would entail savage cuts on employees’ conditions and pay that will never be acceptable to our members. Our members are prepared for the attack on Bus Éireann."
Mr Noone claimed that something similar will follow at the other public transport companies in the CIE Group.
He said: "These attacks must be thwarted, because to fail to do so would undermine decades of work by Siptu members to build efficient and effective transport companies which provide a decent days pay for a decent days work which allow them to support their families in difficult."