Talks between management and union at Acadian Bus Lines, a Maritime regional coach service, broke down Friday before discussions on pay could even start.

The two sides agree on what issue led to the impasse - work assignments, the rules by which drivers' hours are set – but they don't agree on who walked away from the table.

"They walked out on all of us," said Glen Carr of the Amalgamated Transit Union.

"We were in shock. Because we thought we were moving forward."

But Acadian spokesman Marc-Andre Varin said it was the union that shut down negotiations a day and a half early.

"We were advised that the negotiating team on the union side was no longer available to meet to pursue the discussions," said Varin.

The company had offered a new agreement. The union counter-offered. It remains unclear who walked out. They had been working with a federal conciliator.

The union had asked to move beyond work assignments, things including bus drivers' hours, saying those have been sticking points. Varin said those issues need to be resolved before moving on.

The Amalgated Transit Union represents drivers, mechanics and some counter staff at Acadian Lines. (CBC)

"That's critical before we move to anything else," he said.

The union, which represents drivers, mechanics and some counter staff, submitted a new proposal Friday night, and is now willing to tackle work assignments.

"It's the company that needs to come back to the table," said Carr.

But Varin said the union has offered no new concessions on work arrangements, so the company is not yet willing to return to talks.

A possible strike of the 59 union workers could start Nov. 21.