Sydney Airport's outspoken chairman, Max Moore-Wilton, has dismissed growing expectations the federal government will begin work on a second airport for the city within three years.
A day after he played down an infamous royal prank as "shit happens", Mr Moore-Wilton said people needed to be careful that Sydney did not end up with an airport "that goes nowhere".
"When people tell me that the concrete trucks are going to start pouring in the first term of this government, boy oh boy, I wonder what they have been smoking," he said.
Mr Moore-Wilton cited as an example the Canadian city of Montreal, which had built a second airport for the Olympic Games, only to eventually shut it because of a lack of demand.
His comments come amid reports that Treasurer Joe Hockey will include a project for a second airport at Badgerys Creek in western Sydney in the government's first budget.
Mr Moore-Wilton, who is also the chairman of Southern Cross Media, said a second airport would need a "huge government subsidy" in its early years under any funding scenario.
"We want to be careful before we say, 'Yes, fantastic, another piece of infrastructure'," he told The Australian Financial Review and Macquarie Group transport forum in Sydney. "Is it going to be the airport that goes nowhere?"
But Qantas chief executive Alan Joyce told the forum that taking too long to build a second airport would pose a larger cost to Sydney and the country in terms of lost opportunity.
"I don't want an airport too early, but I don't want it built too late. If we don't have a second Sydney airport, eventually by 2060 it will cost over $30 billion to the economy," he said. "We can't be talking for another 20 years because it will be too late."
He cited a joint state-federal study last year highlighting that the landing slots at the existing airport would be filled by 2030 based on a conservative growth rate of 3 per cent per annum.
Mr Joyce said Australia risked losing tourists from Asia to other countries if it did not have adequate airport infrastructure.
Qantas favours a curfew-free airport at Badgerys Creek. Mr Joyce also indicated Qantas was open to basing some of its operations at a second airport, highlighting that flag carriers such as British Airways and Japan Airlines used two airports in the one city.
He also defended the former federal Labor transport minister, Anthony Albanese, describing him as a "great transport minister".
Earlier, Mr Moore-Wilton said he had no doubt Mr Albanese was the "worst aviation minister that we had in my lifetime".