Qantas chief executive Alan Joyce says NSW Premier Barry O'Farrell's opposition to a second Sydney airport is wrong.
Moreover, the NSW Premier's idea of connecting Canberra Airport with Sydney via high-speed rail had little merit, Mr Joyce told the National Press Club in Canberra on Tuesday.
"He is wrong on this and we all know he is wrong on this," Mr Joyce said in response to a question.
"There's no point in building fast train links to places like Canberra and assuming that's going to fix the problem."
While the federal government was pushing hard for a second airport to ease the strain at Mascot, the NSW premier has said previously the community in the Sydney basin should not be subjected to any more aircraft noise.
Meanwhile, Sydney Airport's owners have argued it still had plenty of capacity, pointing to the more efficient use of existing gates and larger aircraft being flown, as well as the arrival of new airlines such as Air Asia X and Scoot.
A federal government report published in March called for a second Sydney airport to be built at Badgerys Creek in the city's west.
Mr Joyce said the site was Qantas' preferred location, while the federal government has advocated Wilton, south of Sydney.
"I would encourage everybody to read that paper because it does show the economic problems that will be created if we don't have a second Sydney airport," Mr Joyce said.
"Anybody that has a view on what is going to happen in any level of growth rate in Sydney knows the damage that it is going to cause not only the NSW economy but the national economy if we don't address this problem."
"It's important for the national economy that something is developed."