New South Wales Labor says it will prioritise Metro links in north-west and south-west Sydney if elected, but won't guarantee other projects announced by the Coalition.
Opposition Leader Chris Minns announced they will explore extending the metro rail line from Western Sydney to Macarthur, and from St Marys to Tallawong.
But won't commission business cases for Westmead to the Aerotropolis, and Bankstown to Glenfield.
Two weeks ago, the government committed $260 million to fast-track business case for all those lines.
Mr Minns says their routes are the most critical due to forecast population growth, which includes the Blacktown and Parramatta local government areas each expanding by 120,000 people by 2041.
He also said they can't support the Bankstown to Glenfield line given the Sydenham to Bankstown segment has "blown-out by $6 billion and is already a year late".
"Literally tens of thousands of people have made life-changing investment decisions about where they will live and work as a result of that [Sydenham to Bankstown line]," he said.
"We still haven't got clarity about whether that project will go ahead at all."
Earlier this month, Minister for Infrastructure, Cities and Active Transport Rob Stokes said their proposal will power the productivity of Western Sydney.
"Our ambition is to complete the Metro network that we started when we first came to government," he said.
"The first step is a coordinated strategic business case to determine which link needs to start first."
Today, Mr Minns questioned the government's ability to deliver.
"I don't believe it's reasonable for the current government to say for the last two elections that they'll build a Metro connection between Sydenham and Bankstown," he said.
"And then on the edge of the third election in a row, say we can't tell you whether it's going ahead or not."
Shadow minister for transport Jo Haylen added that Western Sydney families are often stuck with toll roads as their only choice for getting around.
"Our plans are about ensuring that people can get from Western Sydney CBDs to other Western Sydney CBDs but also to the Western Sydney Airport," she said.
Under Labor, $155 million of state and federal funding will be allocated to the Leppington and Glenfield business case — which includes the Bradfield to Macarthur extension.
They're also pledging an additional $40 million to assess the viability of the St Mary's to Tallawong line.
