In a 14-page ruling Tuesday, the department said Congress pre-empts state and territorial regulation of airline routes, rates and services under the Airline Deregulation Act in 1978.

The ruling was in response to an August petition filed by Hawaiian Airlines Inc. seeking an order that American Samoa may not bar the carrier from continuing to operate flights between Honolulu and Pago Pago.

The petition was filed after Gov. Togiola T.A. Tulafono issued an executive order in July setting a timeframe banning the carrier from operating flights on the route after a replacement carrier is found.

He has accused the carrier of price gouging and mistreating passengers. More than 240 comments and letters were received by the Transportation Department during the public comment period, many echoing the governor's complaints.

The Airline Deregulation Act pre-emption provision "overrides the governor's authority over border control and customs matters at American Samoa, the basis for his claim that he may bar Hawaiian from continuing to serve the territory," the department said.

Hawaiian spokesman Keoni Wagner said the ruling confirms the company's understanding of the law.

"We can now put this behind us and focus on the future for our service to American Samoa," he said.

The Transportation Department urged Hawaiian to meet the governor and American Samoans, "to see if there are ways in which Hawaiian could improve its service."

In an earlier ruling, the department said Hawaiian's current flight frequency on its Honolulu-to-Pago Pago route meets federal requirements while the carrier's fares do not suppress passenger traffic.