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Air Canada has asked federal Jobs Minister Patty Hajdu to refer the dispute to binding arbitration, but she urges both sides to come to an agreement independently.Nathan Denette/The Canadian Press

The rift between Air Canada AC-T and its flight attendants grew wider Thursday as both sides blamed each other for stalling talks and the airline began cancelling flights ahead of a potential strike that could disrupt the remaining summer travel season.

Air Canada and the section of the Canadian Union of Public Employees that represents the airline’s flight attendants held separate news conferences Thursday, accusing each other of delaying negotiations and providing misinformation about the offers on the table.

The union issued a 72-hour strike notice on Wednesday morning, giving more than 10,000 Air Canada and Air Canada Rouge flight attendants the go-ahead to begin striking early Saturday morning. Air Canada responded in kind with a lockout notice and unveiled plans to wind down operations leading up to Saturday.

Air Canada officials said Thursday that several dozen flights would be cancelled that day, followed by about 500 on Friday and a full stoppage of about 1,000 flights each day that flight attendants are not working, affecting about 130,000 customers.

Air Canada plans to cancel flights before a potential strike. Here’s what you may be entitled to

If the work stoppage goes ahead as planned, it could take about a week for Air Canada to resume full operations afterward.

The two sides have been at odds over wages and compensation for hours worked, both accusing the other of cherry-picking numbers in their communications. The union has focused heavily on wages, whereas the airline is considering wider compensation that includes benefits and pensions.

The union is arguing that a proposed 17.2-per-cent pay increase over four years offered by the airline – which would see wages climb 8 per cent in the first year, followed by increases of 3 per cent, 2.5 per cent and 2.75 per cent – isn’t enough to match inflation.

During a press conference Thursday afternoon, Wesley Lesosky, president of CUPE’s Air Canada Component, said flight attendants are currently not paid for preflight work including safety checks, boarding and deplaning. Their wage expectation, he said, is comparable to what some Canadian carriers pay, and a little higher than others.

He said Air Canada has not been at the negotiating table since Tuesday.

“We have been at the table, at the hotel, waiting for them to come back,” Mr. Lesosky said.

A demonstration by more than a dozen members of the Canadian Union of Public Employees prompted Air Canada to end a press conference early as tensions between the two sides continues to mount ahead of a weekend work stoppage.

The Canadian Press

Earlier Thursday, Air Canada held its news conference at a Toronto hotel. Union members, some wearing their flight-attendant uniforms, spilled into the room during the conference, interrupting the event.

Later, Natasha Stea, a veteran flight attendant who represents her colleagues in Montreal as president of CUPE Local 4091 and part of the bargaining committee, spoke to reporters outside the room.

“We just want to get a fair and equitable contract for our flight attendants who are below minimum wage, and we just want to get compensated for all the work that we do,” Ms. Stea said, adding that when their hours worked are weighed against their pay, entry-level flight attendants do not make minimum wage.

Arielle Meloul-Wechsler, Air Canada’s executive vice-president, chief human resources officer and public affairs, said the interruption was unfortunate as the airline tried to provide information to flyers.

”I do think it gives a little bit of insight as to some of the behaviours – when you hear the two versions – it gives you a bit of insight into what we’re dealing with,” she said.

Ms. Meloul-Wechsler said the union had started negotiations by asking for a more than 100-per-cent compensation increase, including other benefits.

Explainer: What’s happening between Air Canada and the flight attendants’ union?

The vice-president said the company’s latest offer amounts to a 38-per-cent compensation increase that would raise benefits, wages and pensions, and would make their flight attendants the best compensated in the country.

She said the union’s wage calculation does not include the ground-pay offer the airline has put forward.

Ms. Meloul-Wechsler also contested the union’s statements that negotiators have not been available.

“We have made offers and responded to every offer CUPE has made, including the last one,” she said.

On Thursday, CUPE leaders accused Air Canada of stalling in anticipation for the government to intervene and force flight attendants back to work.

Air Canada has asked federal Jobs Minister Patty Hajdu to refer the dispute to binding arbitration. In a statement Thursday morning, Ms. Hajdu urged both sides to reach an agreement independently because travellers are counting on the airline. She said she believes deals are best made at the bargaining table.

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Air Canada flight attendants interrupt company executives during a press conference on Thursday.Nathan Denette/The Canadian Press

CUPE national president Mark Hancock said the union will support flight attendants through the process, including if they refuse to return to work in the event of a government order to do so.

Mr. Lesosky said they will review their options if flight attendants are ordered back to work.

Mark Nasr, Air Canada executive vice-president and chief operations officer, said the airline would use any capacity it has to help flyers, including seating them on competing airlines on the same day or within a couple of days of their booking. But that may not be possible, he added.

“It’s the middle of the summer peak, and so we estimate that it will be about 20 per cent of customers who are abroad that we’ll be able to provide accommodation for,” he told The Globe and Mail. “For the rest, unfortunately, the best offers we’ll have will be a full refund of their ticket or the ability to switch their travel date to a later time.”

Grounding and restarting the airline is complex, Mr. Nasr added. Among the tasks are finding parking at packed airports and prepping planes for storage.

When it restarts, planes will be parked around the world and crews will need to be repatriated, he said.

With a report from Vanmala Subramaniam

Are you affected by a possible Air Canada flight attendant strike?

The union representing around 10,000 Air Canada flight attendants could go on strike as early as Aug. 16 after negotiations between the two sides reached an impasse, and the company has already begun to cancel flights. Our reporters want to hear from passengers that have had their plans affected by the possible strike. Have you had to switch your flights or change your travel schedule? Share your story in the box below.