Leaders of the union on strike against Air Canada (AC.TO), opens new tab said on Monday they would risk jail time rather than have cabin crews forced back to work by a federal labor board, raising the stakes in a battle that has disrupted flights for hundreds of thousands of travelers during summer tourist season.

The Canadian Union of Public Employees said the strike would continue until the carrier negotiates on wages and unpaid work, even after the Canada Industrial Relations Board (CIRB) declared the strike unlawful.

"If it means folks like me going to jail, then so be it. If it means our union being fined, then so be it. We're looking for a solution here," said Mark Hancock, CUPE national president, at a press conference shortly after a deadline by the board to return to work expired with no union action to end the strike.

Canadian Prime Minister Mark Carney earlier in the day pleaded for a resolution, which also comes as the Canadian economy is facing tariff pressure from its biggest trade partner, the United States.

"We are in a situation where literally hundreds of thousands of Canadians and visitors to our country are being disrupted by this action," Carney told reporters in Ottawa. "I urge both parties to resolve this as quickly as possible."

The third day of a strike by more than 10,000 flight attendants has stranded passengers and led Air Canada to suspend its third-quarter and full-year 2025 guidance, sending shares down about 1%.

The carrier, which normally carries 130,000 people daily and is part of the global Star Alliance of airlines, had planned to start ramping up operations on Sunday evening, after CIRB ordered the union to return to work and start binding arbitration.

In a message to cabin crew on Sunday seen by Reuters, an Air Canada executive told workers they would be accountable for defying the board's order and not returning to work.

"What your union has not explained is that by not returning to work, you are personally accountable for that decision," said Andrew Yiu, vice president, in-flight service, for Air Canada's mainline and low-cost Rouge service. "To be clear, there is no lockout in place, and the continued strike is illegal."

The flight attendants, who are pushing for a negotiated contract, are striking for wages similar to those earned by cabin crews at Canadian carrier Air Transat (TRZ.TO), opens new tab, and to be fully paid for work on the ground, such as boarding passengers.

Item 1 of 4 Mark Hancock, National President of the Canadian Union of Public Employees (CUPE) which represents striking Air Canada flight attendants, speaks at a news conference in the hotel media room at Toronto Pearson International Airport in Mississauga, Ontario, Canada, August 18, 2025. REUTERS/Wa Lone

[1/4]Mark Hancock, National President of the Canadian Union of Public Employees (CUPE) which represents striking Air Canada flight attendants, speaks at a news conference in the hotel media room at Toronto Pearson International Airport in Mississauga, Ontario, Canada, August 18, 2025. REUTERS/Wa Lone Purchase Licensing Rights, opens new tab

Michael Lynk, professor emeritus of law at Western University in London, Ontario, said there are provisions in the Canada Labour Code that give the board and the court the right to issue fines and sanctions against the union and against individual workers.

UNPAID WORK

Crew are mostly paid when planes are moving, sparking demands by unions in the U.S. and Canada to change the model, and generating some vocal support from passengers on social media.

While passengers have largely expressed support for the flight attendants, some are growing weary of the uncertainty.

Danna Wu, 35, said she and her husband will have no choice but to drive from Winnipeg to Vancouver if the strike persists for a visa appointment. Although she believes Air Canada should pay its attendants more, the master's student at the University of Manitoba added, “it’s not responsible to strike and leave thousands of passengers in such chaos.”

Air Canada's demands on unpaid work follow gains recently won by flight attendants in the United States. New labor agreements at American Airlines (AAL.O), opens new tab and Alaska Airlines (ALK.N), opens new tab legally require carriers to start the clock for paying flight attendants when passengers are boarding.

The government's options to force an end to the strike include asking courts to enforce the order to return to work and seeking an expedited hearing.

The minority government could also try to pass legislation that would need the support of political rivals and approval in both houses of parliament, which are on break until September 15, but has so far been cautious.

"The government will be very reticent to be too heavy-handed because in Canada the Supreme Court has ruled that governments have to be very careful when they take away the right to strike, even for public sector workers that may be deemed essential," said Dionne Pohler, a professor of dispute resolution at Cornell University.

Another option is to encourage bargaining, Pohler said.

The previous Canadian government intervened last year to head off rail and dock strikes that threatened to cripple the economy, but it is highly unusual for a union to defy a CIRB order.