The strikes were triggered Thursday evening when Canada's largest air carrier suspended three ground workers in Toronto allegedly for clapping derisively at Canada's labor minister as she walked through Pearson International Airport. The impromptu work stoppage later spread to baggage handlers at Montreal's Trudeau International Airport.

The minister has become the public face of the Conservative government's efforts to prevent any disruption of Air Canada service because of disputes between the airline and its unions. Ottawa maintains that any work stoppage would harm Canadians and hold back a still-recovering economy.

The wildcat strikes ended after a Friday morning arbitration meeting in which Air Canada agreed to allow the trio to return to their job without penalty.

The union said Air Canada (ACb.TO) also reinstated 37 employees who had walked off the job to protest the suspensions of their co-workers.

"Our disciplined workers are going back to work without penalty - that would indicate to me that the wildcat strike would be over because that's why the guys were staying out," said International Association of Machinists and Aerospace Workers spokesman Bill Trbovich.

The return to work followed a warning by the government that police could be summoned to deal with what it called an illegal work stoppage.

Pearson's website said on Friday morning that 63 of the 689 flights scheduled for departure at the airport had been canceled.

Earlier this month Raitt pushed through legislation that sent the two disputes to binding arbitration, preventing both a threatened strike by the machinists union and lockout of pilots by the airline.

In addition, Raitt took the extra step of asking the Canada Industrial Relations Board to decide whether Air Canada is a service essential for Canadians' health and safety. That essentially blocks either a strike or lockout until the board issues a ruling, and that is expected to take months.

"The government of Canada is opposed to this illegal strike action that is disrupting travel for Canadians," said Raitt in a statement earlier on Friday.

If the union's job action was later ruled by the Canada Industrial Relations Board to be an illegal strike, she warned, employees could face fines up to C$1,000 a day, and the union up to C$100,000 a day.

(Reporting by Susan Taylor and Euan Rocha in Toronto, Randall Palmer in Ottawa and Arpita Mukherjee in Bangalore; Editing by Frank McGurty)

• A Permanent Economic Emergency