The troubled Sydney Metro West line risks becoming an “unmitigated disaster” unless liveability for those living near stops is prioritised, an inquiry into the proposed multi-billion dollar underground rail line has been told.

The Minns government has put aside $13.7 billion over four years for the project – first announced in 2016 by the former coalition government – after warning this year costs had blown out by $12 billion, to a total of $25 billion.

The merits of the line from the city centre to Parramatta are being examined by an independent review and a Labor-chaired parliamentary inquiry, with the government refusing to guarantee the underground rail line’s future.

On Friday, Labor’s Warren Kirby told the inquiry the Metro West project risked repeating errors made with Metro North West, which opened in 2019.

Kirby, the MP for Riverstone, urged more consideration of liveability in high-density areas close to metro stations, which he said had failed with the line through the city’s northwestern suburbs.

“It’s an unmitigated disaster, because we talk about being walkable in the northwest area … two-thirds of the population have two cars or more, people don’t just go from their unit onto a metro to their job and back home,” he said.

On liveability near metro stations, he said: “in my experience, from somewhere that has grown up from zero base to literally hundreds of thousands of people, that is just not playing out”.

The NSW government referred the western metro to the committee to examine its original business case, how the route and station locations were selected and the cause of cost and timeline blowouts.

Stations on the 24-kilometre line are proposed for Westmead, Parramatta, Sydney Olympic Park, North Strathfield, Burwood North, Five Dock, the bays precinct, Pyrmont and the city centre.

Addressing the inquiry, City of Sydney Lord Mayor Clover Moore urged the line be extended eastward with a stop at Zetland given a significant transport infrastructure deficit at Green Square.

“I made it clear to the previous government that Sydney Metro West continuing out to Zetland is essential and should be delivered as soon as possible,” she said.

Moore said with up to 70,000 people set to live in the area by 2036 it was urgent to extend the metro to avoid further congestion on the at-capacity airport link.

The inquiry continues.