Singapore Airlines has accused the Howard Government of becoming "twisted in its own spin" after Transport Minister Warren Truss this week supported a call by United Airlines for an open skies agreement with the US.

The Singaporean attack came as Qantas launched a broadside at United for opposing its application to fly five services a week to Honolulu and accused the Chicago-based carrier of attempting to stop more Australian airlines servicing the US.

Mr Truss made the call after United urged the US Transportation Department to use moves by Jetstar and Virgin Blue to start US services as a lever to negotiate open skies with Australia, removing restrictions on all routes.

United accused Australia of having a protectionist aviation policy that prevented it increasing services on US-Australia routes via Japan.

Singapore yesterday claimed Australian aviation policy was in "complete confusion" after a policy review earlier this year that prevented it launching flights across the Pacific.

"What sort of policy approach is it that sees a minister say he will reconsider Singapore Airlines on the route if the Americans don't grant approvals to Jetstar?" Singapore spokesman Stephen Forshaw said. "Do we now argue to the Americans to keep Jetstar off the route until there's an open skies agreement, so that we get the opportunity?

"This is another case of the Australian Government seeking to pick winners, and it's not the way to run aviation policy."

Mr Forshaw said the only thing that could be read into Mr Truss's comments was that he acknowledged the gap in logic between promoting open skies with the US and keeping Singapore Airlines out of those open skies. "And consumers continue to wonder why it is they're left paying higher fares and suffering a lack of choice when there are airlines willing to give them that choice," he said.

A spokesman for Mr Truss said Australia's view of an open skies agreement was not the same as United's.

He said any such agreement would have to address issues such as government travel policies that favoured US airlines and investment limits.

But the Government recognised this would never happen and still expected that the US would approve the extra Jetstar flight.

Qantas chief financial officer Peter Gregg told an American Chamber of Commerce lunch in Melbourne yesterday that he found United's argument "perplexing, to say the least".

Mr Gregg said United had received $US774 million ($1billion) in grants and loans since September 11, 2001, and the US Government in May last year had agreed to assume the airline's pension liabilities in exchange for up to $US1.5 billion in notes and convertible stock.

This had saved the carrier $US645million a year and amounted to hefty protection.

"We would also like to know what form of open skies United is contemplating, given the US retains some pretty significant barriers to free trade," Mr Gregg said. Overseas airlines trying to invest in US domestic airlines were restricted to 25 per cent of the voting stock and foreign carriers could not compete freely for government travel, he noted.

"I would suggest that United is not so concerned about Jetstar's one extra service to Honolulu," he said.

"Rather, perversely, it seems to be using this negotiating tactic to make it as difficult as possible for another Australian airline to enter the route in future."