Premier Pauline Marois said she is willing, although reluctant, to invoke back-to-work legislation in the labour dispute that has halted construction across the province for the past eight days.

Talks between one key sector — industrial, commercial and institutional construction — fell apart at 2:30 a.m. on Monday after a weekend negotiating blitz.

Marois interrupted Fête nationale celebrations to meet briefly with reporters and appoint a special mediator to pave the way to an agreement in that sector.

"I think that it is possible to have a solution in the next days," Marois said on Monday afternoon.

But if no progress is made by next week, the premier said she will reluctantly invoke back-to-work legislation.

The head of the Quebec Federation of Labour's construction wing, Yves Ouellet, is acting as spokesman for the alliance of the five construction unions.

Ouellet said the alliance is looking forward to working with a mediator.  However, he says construction bosses would rather see back-to-work legislation imposed on the unions than negotiate a deal.

"We can ask them why they want the special law," Ouellet said. "But a special law is never there to help."

Road workers return to job sites Tuesday

On one key front, there has been progress.

There is a tentative agreement in the civil engineering and roadwork sector, which means 40,000 workers on major road and infrastructure projects will return to work on Tuesday.

A third sector — the residential building industry — is still in talks.

More than 175,000 workers walked off the job a week ago. Their demands include salary increases and adequate compensation for overtime hours.