The Turnbull government has dampened expectations it might back a high-speed rail link between Melbourne and Brisbane.
“There is a lot of work to be done before that would ever come to fruition,” the assistant minister for cities Angus Taylor said on Monday.
The only way such major projects could be progressed was through transforming the ways proposals were planned, financed and delivered, he said.
That could mean using increased land value from major transport infrastructure as a potential source of funding.
Prime Minister Malcolm Turnbull says the approach is not a radical plan.
“It is a sensible old plan that’s been forgotten – that’s how railways were financed in the 19th century,” he told reporters in Karratha, Western Australia.
Opposition Leader Bill Shorten accused the prime minister of engaging in cheap talk.
“Yet again this is a desperate Malcolm Turnbull clutching at straws to try and shake off the tag of being a do-nothing prime minister,” he told reporters in Melbourne.
Opposition transport spokesman Anthony Albanese says the funding proposal is nothing new and he urged Mr Turnbull to back his private bill establishing a High-Speed Rail Authority.
“You actually need a structure that will work, to do the planning work, preserve the corridor,” he said.
A Labor-commissioned report into high-speed rail identified the need for 82km of tunnels, including 67km within Sydney, but projected an economic benefit of $2.15 for every dollar invested between Sydney and Melbourne.
Projects needed to be built using both private investment and taxpayer dollars, Mr Albanese said.
“Anyone who comes and tells you, you can do this for free is fantasising,” he said.
Another option being considered by the Turnbull government is to levy a so-called betterment tax on property owners who receive a substantial financial boost from the new transport infrastructure.
Mr Taylor said betterment taxes had been used in Hong Kong, London and, in part, for the Sydney Harbour Bridge.
Victoria’s transport minister Jacinta Allan was sceptical of the latest discussion, saying regional residents like her could set their clock by the annual conversation.
“But I think it is something that needs to be explored and we’d certainly support that being undertaken,” she told reporters.