After Amazon announced it would shutter its Quebec warehouses, costing 1,700 workers their jobs, a Canadian union said it would strike back.

Amazon.com Inc.’s decision to close all seven of its warehouses in the Canadian province of Quebec and terminate more than 1,900 workers is prompting legal action from the affected union.

Canada has warned Amazon.com that it is reviewing business ties with the company’s cloud-computing unit following Amazon’s decision to shut down its warehouses in Quebec, leading to the layoff of 1,700 workers.

A union that represents some Montreal Amazon workers said it will petition a court to compel the company to reopen the warehouses and reverse the job cuts.