Premier Gladys Berejiklian has used the final day of the state election campaign to attack Labor's promise to scrap stage one of the F6 extension,
Labor's policy is to divert the $2.4 - $2.6 billion funding into improving public transport in Sydney's South, including rail services on the Illawarra and South Coast lines.
The party's candidate for Heathcote Maryanne Stuart said Labor would "invest in public transport over toll roads".
"Improving the Illawarra South Coast rail lines will be the priority over funding a very expensive and and unnecessary F6 toll road," she said.
"A series of leaks to journalists have revealed widespread irregularities in the F6 project, including that the toll will be $10 in 2024 and run for 35 years, that rail alternatives were not considered, and that six exhaust stacks will be needed throughout St George and Sutherland Shire."
Ms Berejiklian, who is expected to visit the Heathcote electorate on Friday, said Labor would "turn its back on the communities of southern Sydney and cause traffic gridlock for tens of thousands of commuters by dumping the F6 Extension if elected"
"A vote for Labor is a vote to scrap the F6 extension," she said.
"They have said it will not proceed should they win the election on Saturday, but we know this project is so important because it will allow people to spend less time sitting in traffic and give them more time back in their lives.
"The F6 extension will allow drivers to bypass 23 sets of traffic lights and save up to 15 minutes on each journey.
"During Labor's last 16 years in office, they repeatedly announced plans for the F6 corridor but delivered nothing.
"Now, Labor have once again said they will scrap it, and instead have a talkfest on what to do with the money.
Roads Minister Melinda Pavey said Labor had "floated a whole bunch of thought bubbles on what they will use this money for, including a Thirroul tunnel that would deprive communities south of Waterfall of train services".
"What's worse, even Labor admit that these funds are nowhere near enough to build that," she said.
Ms Pavey said the toll for the first stage of the F6 extension was planned o be $1.77 each way for cars.
Travelling on it will also involve using the WestConnex motorway, for which motorists will pay a minimum of $4.53.
"Users of the F6 extension will also be eligible for the NSW Government's half-priced tolls package, should they spend more than $15 a week on tolls, or free registration, should they spend $25 or more a week on tolls," Ms Pavey said.
"The design for stage one of the F6 extension includes connection tunnels to facilitate future components of the F6 between Kogarah and Loftus, which are in development."
Twin tunnels from Arncliffe to Kogarah make up the first stage.