The operator of Sydney's main airport Tuesday ruled out involvement in building a second major airport for the city, citing financial risks, leaving the Australian government to develop the project.
Canberra last December announced plans for another airport in Sydney, ending decades of indecision over a facility that will initially handle 10 million passengers a year.
Badgerys Creek in the western suburbs had already been selected as the site.
It is scheduled to open in 2026, easing pressure on Sydney's Kingsford Smith Airport -- the main gateway into Australia -- which is reaching capacity.
The listed Sydney Airport Group, owner of Kingsford Smith, had the right of first refusal to build and operate the new multi-billion dollar Western Sydney Airport (WSA) but declined.
"Despite the opportunities that WSA will present, the risks associated with the development and operation of WSA are considerable and endure for many decades without commensurate returns for our investors," the company said in a statement to the stock market.
Prime Minister Malcolm Turnbull said the government would instead take on the project, with details set to be revealed in next week's federal budget.
"The airport will be a major catalyst for jobs and economic growth in Western Sydney, injecting more than Aus$1.9 billion ($1.43 billion) into the economy during the construction phase alone," he said.
"It is expected to deliver 9,000 new jobs to Western Sydney by the early 2030s, and 60,000 in the long-term."
The first stage will see one runway constructed, able to handle Airbus A380s and 10 million people each year, with a second expected to be needed by 2050.
Kingsford Smith Airport, which is eight kilometres (around five miles) from the city centre, handled 39.7 million travellers in 2015 and is reaching its limit. Passenger numbers through Sydney are forecast to more than double in the next 20 years.
It is also subject to flight restrictions between 11 pm-6am. Badgerys Creek, 45 kilometres west of Sydney's central business district, is expected to be curfew-free given that fewer people live nearby.
Badgerys has been a potential site since 1986, with the government buying about 1,800 hectares (4,446 acres) in the area and the surroundings kept largely free of development since then.