Air Canada and its unionized flight attendants remained at odds on Friday, despite government pleas for both sides to return to bargaining to avert a strike that would upend travel for tens of thousands of passengers.

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 expects to cancel the majority of its estimated 700 daily flights on Friday, ahead of a planned Saturday strike by unionized flight attendants, leaving some 100,000 passengers scrambling to make alternative travel plans.