Air Canada suspended plans to restart operations Sunday after the union representing 10,000 flight attendants said it will defy a return to work order. The Canada Industrial Relations Board ordered airline staff back to work by 2 p.

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 cancelled hundreds of additional flights on Sunday after the union representing its flight attendants announced the workers would remain on strike in defiance of a back-to-work order. The Canadian Union of Public Employees said it filed a challenge in Federal Court on Sunday to an order by the Canada Industrial Relations Board that said its members must return to work by 2 p.