TORONTO — The union for 10,000 striking Air Canada flight attendants said Monday they won’t return to work even though the strike, now in its third day, has been declared illegal. The strike at Canada’s largest airline is affecting about 130,000 travelers a day at the peak of the summer travel season, and the two sides remain far apart on pay and other issues.

Air Canada said rolling cancelations now extend to Tuesday afternoon after the union defied a second return-to-work order. The airline said earlier said operations would resume Monday evening but the union president said that won’t happen.

“If Air Canada thinks that planes will be flying this afternoon they are sorely mistaken. That won’t be happening today,” said Mark Hancock, national president for Canadian Union of Public Employees, or CUPE, which also represents some non-public sectors.

“We will not be returning to the skies,” he said.

Defying a second return to work order

The Canada Industrial Relations Board had declared the strike illegal earlier on Monday and ordered the striking flight attendants back on the job. But the union said it will defy this second return to work order, after an earlier one had been ignored. The earlier one also ordered the union to submit to arbitration.

The board, an independent administrative tribunal that interprets and applies Canada’s labor laws, had said the union needed to provide written notice to all of its members by noon Monday that they must resume their duties.

“If it means folks like me going to jail than so be it. If it means our union being fined than so be it,” Hancock said, “We’re looking for a solution here. Our members want a solution here but solution has to be found at the bargaining table.”

It was not immediately clear what recourse the board or the government have if the union continues to refuse.

Labor leaders are objecting to the government’s repeated use of a law that cuts off workers right to strike and force them into arbitration, as the government has already done in recent years with workers at ports, railways and elsewhere.

“We are in a situation where literally hundreds of thousands of Canadians and visitors to our country are being disrupted by this action,” Canada’s Prime Minister Mark Carney said. “I urge both parties to resolve this as quickly as possible.”

Carney said his jobs minister would have more to say later and added that it was disappointing that the talks have not led to a deal. He stressed it is important that flight attendants are compensated fairly at all times.

The labor board previously ordered airline staff back to work by 2 p.m. Sunday and for the union to enter arbitration, after the government intervened. Air Canada then said it planned to resume flights Sunday evening. But when the workers refused, the airline said it would resume flights Monday evening instead. However, there was no sign CUPE would relent.

Air Canada operates around 700 flights per day. The airline estimates 50,000 customers will be disrupted.

Air Canada chief executive Michael Rousseau said he’s still looking for a quick resolution.

“We’re obviously hoping we can go tomorrow, but we’ll make that decision later today,” Rousseau said on BNN Bloomberg shortly after the union announced it would continue with the strike.

Disrupted tourists, stranded passengers

Tourists John and Lois Alderman said Air Canada has told them they could be stranded in Toronto for another four to five days while they wait for a flight back home to Manchester, United Kingdom.

“I’m a diabetic and I’m going to run out of insulin in about four days,” John said at Pearson International Airport. “That’s going to cause a problem.”

Flight attendants walked off the job around 1 a.m. EDT on Saturday, after turning down the airline’s request to enter into government-directed arbitration, which allows a third-party mediator to decide the terms of a new contract.

Air Canada and CUPE have been in contract talks for about eight months, but remain far apart on the issue of pay and the unpaid work that flight attendants do when planes aren’t in the air.

The airline’s latest offer included a 38% increase in total compensation, including benefits and pensions, over four years, that it said “would have made our flight attendants the best compensated in Canada.”

But the union pushed back, saying the proposed 8% raise in the first year didn’t go far enough because of inflation.

Passengers whose flights are impacted will be eligible to request a full refund on the airline’s website or mobile app, according to Air Canada.