STM bus drivers and metro operators have voted overwhelmingly in favour of a strike mandate.

The union members voted Thursday night 99 per cent in favour of pressure tactics including a general unlimited strike.

The vote doesn't necessarily mean there will be a strike, though, and if they do decide to go on strike, drivers will be required to provide a minimum level of service as determined by a tribunal.

The STM issued a statement Thursday evening saying that seven days’ notice would be required to hold a general strike.

"The management of the STM is not respectful of the 4,500 employees who provide millions of trips for Montrealers. In too many cases the circuits are completely unrealistic. These poorly planned trips stress passengers who are frustrating drivers and they pay the price for poor planning that creates serious workplace health and safety issues, " said union chapter president Renato Carlone in a statement.

The union argues that drivers are working in increasingly difficult conditions which include many construction sites, of the road with a growing number of cyclists and the lowering of speed limits in many areas. They say these issues are not taken when designing and timing routes.

"This situation can easily be corrected if management makes a formal commitment to tackle this problem that affects both the public and our members," said Carlone.

Drivers have been without a contract since January, and they say that after 23 negotiation sessions they are at an impasse.

Altogether 4,500 drivers are represented by CUPE local 1983, which belongs to the Quebec Federation of Labour.

The drivers' vote comes one day after STM maintenance workers announced they would be working to rule next week, refusing overtime, not acknowledging last-minute shift changes, and engaging in other pressure tactics.

Those tactics will last six days, beginning Monday, as the group calls on the STM to hire more workers so they can have a better work-life balance.

The labour tribunal has agreed to their conditions, saying that the only shift changes acceptable will be to replace a sick employee. The union has also said that emergency crews will have a full complement of employees for every shift.

The STM drivers haven’t gone on strike in more than ten years.