Air Canada said on Tuesday it has asked for federal government intervention in contract talks with its flight attendants union, after the airline declared an impasse in the negotiations.

Air Canada flight attendants' union would need to notify their intention by end of the day Tuesday if they intend to walk off the job on Saturday.

In a response letter from the union dated August 12 and obtained by The Globe, Wesley Lesosky, president of the Air Canada Component of CUPE declined the proposal to proceed to binding arbitration, calling it “not an appropriate path in this round of bargaining.” He urged Air Canada to continue to negotiate at the bargaining table.