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.

Air Canada said on Thursday it expects to cancel several dozen flights by day's end and around 500 flights by the end of Friday affecting 100,0000 passengers, ahead of a planned Saturday strike by its unionized flight attendants.

Air Canada has canceled most of its flights over the next few days to prepare for a strike by flight attendants. Some travelers may end up stranded as a result.