A spokesperson for Bus Eireann is accusing the SIPTU and NBRU unions of having a "cavalier" attitude to the lives of passengers, and is urging them back to the talks table.
The travel plans of up to one million people are being affected this morning because of the 48-hour strike action at Dublin Bus and Bus Eireann.
Nicola Cooke said the only way to resolve the row over privatisation is at with talks at the Labour Relations Commission.
Spokesperson for the NBRU Dermot O'Leary said it was up to the LRC to decide whether talks would resume.
"(The) company that has an inability to get all of the stakeholders together," he said. "It's appalling that it's ended up in a situation where those people can't get to work or school."