CALGARY, Alberta -- WestJet Airlines announced Monday that it had apologized to rival Air Canada and would pay US$14 million (C$15.5 million) over a campaign of Internet skullduggery it admits had the blessing of "the highest management levels" at the company.

In a joint announcement by the two carriers Monday, WestJet acknowledged that "in 2003-2004, certain members of WestJet management engaged in an extensive practice of covertly accessing a password protected proprietary employee Web site maintained by Air Canada to download detailed and commercially sensitive information without authorization or consent from Air Canada."

Air Canada filed a US$199 million (C$220 million) lawsuit last year alleging WestJet wrongfully used the Air Canada employee Web site to get information on passenger loads. Air Canada said the information could be used to identify its most profitable routes and times.

WestJet countered with accusations that Air Canada hired private investigators to sift through an executive's trash and then had a U.S. firm digitally reconstruct shredded documents.

The discount airline accused the country's largest airliner, Air Canada, of disclosing documents related to the litigation in an attempt to embarrass WestJet.

Calgary-based WestJet said Monday it would pay US$5 million (C$5.5 million) to cover Air Canada's investigation and litigation costs and would make a US$9 million (C$10 million) donation to children's charities across the country at Air Canada's request.

"This practice was undertaken with the knowledge and direction of the highest management levels of WestJet and was not halted until discovered by Air Canada," the companies stated.

"This conduct was both unethical and unacceptable and WestJet accepts full responsibility for such misconduct. WestJet sincerely regrets having engaged in this practice and unreservedly apologizes to Air Canada and (CEO of parent corporation ACE Aviation Holdings Inc.) Mr. Robert Milton."