The Montreal-based airline, which transports about 130,000 customers a day, said the union representing flight attendants made a recent counteroffer seeking “exorbitant” pay increases, and has rejected an offer to enter third-party binding arbitration.

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 contract negotiations with its flight attendants have come to a standstill, which could result in the issuance of a statutory 72-hour strike or lockout notice occurring at 12:01 a.m. EST on Aug. 13. Canada’s largest airline explained it offered a 38% increase in compensation over four...