New railway stations will be created at Five Dock, North Burwood and North Strathfield as part of the promised Metro West rail line, which the Berejiklian government has committed to beginning next year if the Coalition wins the upcoming election.

NSW Premier Gladys Berejiklian and Transport Minister Andrew Constance announced the Coalition would inject $6.4 billion into the transport infrastructure project, which is expected to reduce travel times between Parramatta and the Sydney CBD to 20 minutes, with trains running every two minutes.

Construction on the Metro West rail line is expected to begin next year.

"We’ve been working day and night to bring forward the day of start of construction, and what I'm really excited about is not only will construction start next year, we’re likely to have the tunnel boring machines in the ground in 2021," Ms Berejiklian said.

Ms Berejilkian made the announcement at Westmead, one of the already-confirmed stops for the train line, which will also stop at Parramatta, Olympic Park, and the Bays Precinct.