As Air Canada cancelled flights on Thursday ahead of a possible flight attendants' strike, the union representing those workers accused the federal jobs minister of speaking "on behalf" of the company amid a contentious labour dispute.

Air Canada began cancelling flights on Thursday after receiving a strike notice from the flight attendants' union, warning all operations could be shut down by Saturday. Chief operating officer Mark Nasr told reporters Thursday that the airline had begun "a gradual suspension of Air Canada and Air Canada Rouge operations.

Mark Nasr, Air Canada's chief operations officer, said that cancellations would go from "several dozens" on Thursday, to some 500 by the end of Friday, to the airline being "completely grounded" at the start of the strike on Saturday, in the absence of a resolution.