Picketers march around the departures level at the Vancouver International Airport in Richmond, B.C., on Sunday, Aug. 17, 2025. Air Canada made the call to halt a return to operation as flight attendants continue to strike. THE CANADIAN PRESS/Ethan Cairns

Air Canada says it has suspended plans to resume limited operations after the union representing the airline's flight attendants said Sunday it will defy a federal back-to-work order for binding arbitration to end the work stoppage.

Air Canada flight attendants said on Sunday they will remain on strike and challenge a return-to-work order they called unconstitutional, defying a government decision to force them back to their duties by 2 p.