Calls for overweight passengers to pay a surcharge to fly with Australian airlines fell flat with the major carriers all rejecting the idea.

It followed former Qantas chief economist Tony Webber saying obese passengers should pay more to cover extra fuel costs incurred by airlines.

"When the passengers weigh more, or where there's extra weight on the aircraft, that generates more fuel burn and higher fuel costs," he told ABC radio.

"Airlines are really preoccupied at the moment with reducing their fuel costs because the price of jet fuel is so high at the moment.

"On a flight from Sydney to London-Heathrow via Singapore, you're only looking at (a surcharge of) between five and 10 bucks."

He cited Indonesia as an example where he said authorities often weigh the baggage and the passenger at the same time.

"You'd have to work out the total weight of the baggage and the person and then have a critical weight, say 90 kilos (200 pounds) or 100 kilos, above which you'd impose a surcharge," he said.

But Australian carriers on Thursday said they had no plans to go down this road.

A spokeswoman for his former employer said: "Qantas currently has no plans to introduce a surcharge nor does it have a policy in place for customers of size."

Virgin also poured cold water on the idea.

"Such a notion is not under consideration at our airline," a spokesman told reporters, while Tiger Airways replied: "In short, no," when asked if it would ever consider the proposal.

The idea of a weight tax has been around for years with some airlines around the world charging for a second seat if passengers are unable to lower both armrests.