BUS Eireann passengers may face travel chaos from Sunday after more than 1,000 staff served notice of industrial action.
Members of the National Bus and Rail Union (NBRU) have backed industrial action – which could mean a strike – by 92pc in a ballot.
A smaller union, the Transport Salaried Staffs Association, also voted by 73pc for industrial action if the company forges ahead with a cost-cutting plan.
The company's other big union, SIPTU, will tomorrow reveal if its 1,000-plus members will throw their weight behind the campaign.
NBRU leader Michael Faherty warned there would be no services on Sunday if the company went ahead with the cuts, although this means the union could not give legal notice of seven days.
"Staff won't be working these changes on Sunday and the company better take it on board," he said.
Bus Eireann said it would "try and maintain a level of service" but could not "firm up" contingency plans as the union had not told the company what type of industrial action it would take, and when.
Both sides seem set for a collision course as they refused to compromise last night.
Bus Eireann took a hard line with the union, and said it planned to go ahead with the cuts to premium and other payments this weekend.
"We still intend to enforce the changes on Sunday," said a spokesperson.
"We are at this process since June, when we first announced the plan and went to the Labour Relations Commission, but the unions would not negotiate on the key savings, which include changes to overtime, shift and premium pay rates."
After this, the company told staff it would go ahead and impose the cuts without union agreement from January 13.
It said the NBRU's letter serving notice of industrial action did not specify when industrial action would take place, or what form it would take.
This poses problems for Bus Eireann if it tries to seek an injunction to prevent any action.
It insists it has an in-house agreement with the union that means it should give 30 days' notice before taking industrial action.
"It is critical for our customers that the NBRU inform the company of what industrial action they are planning to take and when," said the spokesperson.
The cuts are part of a €9m payroll savings plan as the company predicts losses of €16m this year.