Air Transat flight attendants have rejected the latest contract offer from their employer and approved a mandate for a general strike.

The roughly 1,500 flight attendants, who are represented by CUPE, voted 93 per cent in favour of a strike mandate, the union said in a statement released Thursday night.

CUPE said the Montreal-based company has "continued to ask for cuts that simply are not justified by its financial situation."

Among the concerns were pensions and shift duration, the union said.

The union also said they asked the federal Department of Labour to appoint a conciliator to help with negotiations on April 21.

The federal department says a conciliation officer's role is "that of a mediator with no special powers."

The conciliator is given 60 days to help the employer and the union as they try to reach a settlement.

If the feuding parties can't come to agreement within the 60-day period, they go through a 21-day "cooling off" period, the department says.

After that period passes, workers can launch a strike and employers can lock out employees.

The union said it was still hoping for a negotiated settlement, and the earliest a strike could be launched is late July.

Air Transat representatives were not immediately available to comment.

The news of the strike mandate comes after Air Canada and the union representing striking customer service and sales agents came to a tentative agreement after a three-day walkout.

The Air Canada deal came shortly after the federal government tabled legislation aimed at forcing the airline employees back to work — a move opposed by the union representing the striking Air Canada workers.

With files from The Canadian Press