The coalition in February said it was starting the $260 million process of delivering four new Metro lines at Tallawong to St Marys, Westmead to the Aerotropolis near Badgerys Creek, Bankstown to Glenfield via Liverpool, and Macarthur to the Aerotropolis.
Labor, meanwhile, says it will halt the business cases for two of the Metro lines - the link to the new western Sydney airport and Bankstown to Glenfield - if it forms government later this month, citing cost blowouts.
Campaigning in Rouse Hill on Wednesday, Mr Perrottet stood by the timeline on the transport links, part of the Sydney Metro network that started with the Chatswood to Tallawong northwest line in 2019.
"These are projects that make a real difference," he told reporters.
"You can't build them all at once," he said, labelling Labor's plan to scrap part of the system as "short-sighted".
"We have to future proof western Sydney," Mr Perrottet said.
Earlier, Labor vowed to deliver rapid bus services to connect Campbelltown, Liverpool and Penrith to the new Western Sydney Airport and Aerotropolis precinct.
Labor said it would procure 84 buses - to be built in western Sydney - for the services, committing $305 million over three years.
"We have a situation where a new airport will be open, thousands of jobs created but people wanting to work at the airport don't have access to public transport services to get there," Opposition Leader Chris Minns said.
Mr Perrottet hit back, saying the coalition was already planning to "bring on" buses for the new airport, describing the Labor plan as "short-term thinking".
"You don't say 'I'm going to cancel the future of public transport for western Sydney because we're bringing on buses on in 2026'," he said.
"We are committed to a transport revolution."
The transport spat comes as a new poll, published in The Sydney Morning Herald on Wednesday, points to a clear Labor victory at the March 25 election.
The Resolve Political Monitor survey of 803 eligible voters found Labor's primary vote had lifted one percentage point to 38 per cent, while the coalition's had dropped two points to 32 per cent
With 93 seats up for grabs, the data points to an overall swing of seven per cent to Labor - enough to deliver the 47 seats required to form a majority government.
However, Mr Perrottet remains the preferred premier over Mr Minns, at 38 per cent to 34 per cent.
Some 76 per cent of voters polled said they were committed to who they planned to vote for, while 24 per cent remained uncertain.
With just a week until candidate nominations close, the NSW Liberal Party is yet to preselect candidates in 17 seats, while Labor still has five outstanding.
