The Brisbane-based international and domestic airline, formerly known as Strategic Airlines, said all flights had been canceled and the airline would not be accepting new bookings because it could no longer pay its bills. Voluntary administration in Australia is similar to bankruptcy protection in the U.S., and can buy a company time to trade out of its financial problems.

"It currently appears that there are no funds available to meet operational expenses so flights will be suspended immediately," the airline said in a statement. Passengers who bought tickets with credit cards or had travel insurance may be given a refund, the airline said.

Around 4,000 passengers were overseas with Air Australia round-trip tickets, voluntary administrator Mark Korda said. Some of those affected were stranded in Honolulu and Phuket, Thailand.

"Overnight, the company was unable to refuel its planes in Phuket," Korda told Australia's Fairfax Radio. "The directors appointed us at 1:30 this morning and the boys have been working throughout the night to deal with what's a very difficult situation."