Canada's government stepped in four times to aid seven companies last year, stopping strikes using an obscure Labour Code provision. A similar decree on Sunday failed, however, as Air Canada's flight attendants refused to obey and stayed on strike for three days.

Air Canada has suspended plans to restart operations after the union representing 10,000 flight attendants decided to defy a return-to-work order

Air Canada has already begun canceling flights after hitting an impasse in contract negotiations with the flight attendants' union as a possible strike looms. Earlier this week, the union issued a notice of intention to strike,

After months of stalled negotiations, 10,000 Air Canada flight attendants walked off the job early Saturday morning. The federal government stepped in hours later to order binding arbitration, forcing an end to the strike — or so they thought.