Bus Éireann has insisted that it plans to go ahead with implementing cost-cutting measures on Sunday.
The company is facing strike action from three separate trade unions.
Members of SIPTU, the Transport And Salaried Staff Association and the National Bus and Railworkers Union have voted to down tools next Thursday if CIE pushes through changes to work practices from this weekend aimed at saving €9m.
Andrew McAlindon from Bus Éireann said that the union had plenty of time to come to the table and negotiate changes.
"Any industrial action would be completely counter-productive," he said.
"All it will do is increase our losses and disrupt services for customers.
"And if we increase our losses, then unfortunately it's counter-productive for staff because all that will mean is that we'll have to make further cuts in terms of terms and conditions."