Montreal Mayor Gerald Tremblay is teaming up with the mayors of Winnipeg and Mississauga, Ont., to pressure Ottawa to intervene in the dispute between the aircraft maintenance company Aveos and Air Canada.

Their letter to Prime Minister Stephen Harper asks him to call an emergency meeting between the two companies to protect jobs affected by the dispute.

The mayors argue Air Canada is obliged by law to continue to operate maintenance centres in all three cities under the Air Canada Public Participation Act.

They say they have spoken to Air Canada's president, and he has agreed to collaborate and discuss the issue.

Aveos annouced this week it is shutting three main plants in Vancouver, Winnipeg and Montreal, as well as other facilities in Edmonton, Calgary, and Trenton and Mississauga in Ontario.

Almost all its 2,600 unionized employees across the country were laid off and its assets are being liquidated because of a lack of work from Air Canada. Aveos gets about 90 per cent of its business from the airline.

Marcel St. Jean, president of Local 1751 of the International Association of Machinists and Aerospace Workers, said Wednesday the overall number may be closer to 3,000 when non-unionized workers are included.

Excerpts from the mayors’ letter:

"As mayors, on behalf of our citizens, we call upon your leadership to urgently convene a meeting of the parties concerned in order to find solutions that would respect the spirit of the law, thereby protecting the thousands of jobs directly and indirectly affected.

"In so doing, we would maintain the Canadian aeronautics industry's rank as one of the best in the world as well as help consolidate the country's economic performance.

"In the current, fragile economic situation we are experiencing, it is our duty to safeguard the leading edge technology infrastructures and jobs that make Canada one of the worldwide leaders in the field of aeronautics.

"Even more fundamental is the necessity to respect rule of law as the laws upon which this country built both its prosperity and its trust in itself."

'Situation unacceptable'

The mayors said Air Canada has the obligation to maintain the maintenance and repair centres in Montreal, Winnipeg and Mississauga.

They called the situation unacceptable.

Air Canada is not a private company like any other, they argue, as it is the country's national air carrier.

"Its obligations under law come as a compensation for the protection of its privileges as such. This has also, and very recently, enabled your government to intervene in the carrier's labour relations," the letter reads.

Air Canada was transformed from a Crown corporation into a private company in 1988.

Aveos says a drop in work has cost it millions of dollars in revenue in recent months.

The airline offered $15 million in emergency funding Monday afternoon, but Aveos said it wasn't enough to keep the company going.

Quebec Premier Jean Charest has already threatened to sue the federal government over the Aveos shutdown, while the province's national assembly unanimously passed a motion earlier this week promising to do everything it could to help the company's employees.

With files from The Canadian Press