The National Bus and Rail Union is to ballot members in Dublin Bus and Bus Éireann today for industrial action if both companies press ahead with planned cutbacks.
The cutbacks will result in the loss of over 600 jobs and 270 buses will be withdrawn.
Bus Éireann is to cut 320 jobs and Dublin Bus has announced 290 job losses as part of a series of cost-cutting measures.
Bus Éireann says its fleet is to be reduced by 150 vehicles.
The company says its cost effectiveness plan is necessary to ensure its success in 'a very challenging economic environment'.
In addition to the job cuts and reduction in its fleet, the plan includes a pay freeze up to the end of 2009 as well as the deferring of payment of the terms of Towards 2016.
Bus Éireann says it hopes that savings from the plan will restore the company to a strong financial position by the end of 2010.
Dublin Bus is also withdrawing 120 buses, which is 10% of its fleet.
It said no routes will be removed, but some services would be amalgamated and that the frequency of buses would be adjusted in some areas.
