Unions at Bus Éireann will meet this week to discuss strike action at the company.
The NBRU has accused the firm of playing a game of chess with employees, after the company announced a series of cutbacks to come into force next month.
Bus Éireann says it lost several million euro last year and now runs the risk of becoming insolvent.
General Secretary of the NBRU Dermot O'Leary said the timeline of events was dictated by the company, after they issued the notice on Friday announcing pay cuts.
The unilateral cuts to all premiums come in on February 20, affecting sick pay, overtime and Sunday rates.
Bus Éireann acting CEO Ray Hernan said workers will see their pay cut by 10%, Sunday premium pay slashed by 80%, shift premium payments scrapped, and further cuts to sick pay and overtime.
Dermot O'Leary said: "We'll meet with our union colleagues next week. There will be industrial action."