Summer travelers are facing uncertainty as the clock winds down on a possible strike by Air Canada flight attendants, which the airline said would force it to cancel almost all of its scheduled flights as soon as Saturday.

Air Canada has canceled hundreds of flights — many of them international flights — as a potential strike by flight attendants looms.

Air Canada's flight attendants were poised to strike on Saturday as the carrier cancelled hundreds of flights impacting more than 100,000 passengers ahead of a threatened work stoppage that could shut down service.