A Canada Post strike could be triggered starting at midnight if no agreement is reached during the day on Sunday.

The Canadian Union of Postal Workers (CUPW) filed a strike notice earlier this week after ten months of negotiations to renew collective agreements.

Lise-Lyne Gélineau, president of CUPW's Montreal chapter, explained that members do not want to go on strike, but that the ball is in the employer's court.

While the growing popularity of online shopping has been accompanied by an increased workload for postal workers, on Saturday, Canada Post refused a new proposal that would see postal routes modified according to the volume of mail, according to Gelinas.

In an email to The Canadian Press on Sunday, Canada Post defended itself by stating that it was responding to many of the issues raised by the union, and has already tabled a significant offer that included wage increases, as well as the improvement of job security and social benefits.

CUPW announced that a possible work stoppage would take the form of a series of rotating strikes that would affect provinces or regions one at a time. However, the union has not yet specified where such a strike would be triggered first.

Canada Post said that if there were to be a strike, its activities would continue with possible "minor delays." The union says they're committed to continuing delivery of pension and social assistance checks, as it has done in the past.

The Canadian Union of Postal Workers, which in Quebec is affiliated with the FTQ, has some 50,000 members in Canada, including 42,000 in urban areas, and 8,000 in remote sectors.