The National Bus and Rail Union has accused Bus Éireann of positioning itself to become a low-wage operator in order to compete in future tendering processes for bus routes.
Arriving at talks at the Workplace Relations Commission, NBRU General Secretary Dermot O'Leary queried the company's ambition to secure saving of €30m, saying the losses at Expressway were only €8-9m.
He said the only reason the company would seek savings of €30m was to become a low-wage operator to get involved in the "cut-throat" tendering business in 2019 and 2024.
SIPTU Divisional Organiser Greg Ennis said it would be difficult to secure a deal given that key stakeholders including the Department of Transport the National Transport Authority and the Department of Social Protection were not at the table.
Strike action has been suspended to allow for talks which will continue on Monday and Tuesday.