He also conceded he is yet to undertake a business plan to determine whether the project is viable but would do so before the November election. "As far as I am concerned, I am going to the public with a very clear view as to how I want to grow the state," he told radio station 3AW on Wednesday. "One of the things the business case will do is certainly identify efficiencies in how we can build, and some of the construction and timing and sequencing." Mr Guy said some train lines would have to be closed for periods of time due to construction works, but it was necessary to invest in heavy rail to "decentralise" Melbourne's growth, with the population in the city soaring by 2700 people a week. "I'm seeking a mandate from Victorians to lead a government that will decentralise our growth and take the pressure off Melbourne - this is how I want to do it," he said.

He also defended the project's cost efficiency. "It's a lot of money $15 to 19 billion ... but over a ten-year period it's realistic, it can be achieved," Mr Guy said. He added it could cost about a "million dollars per kilometre" to fix some sections of the tracks so trains could reach the speeds envisioned by the opposition. High-speed train services from Geelong to Melbourne would take as ­little as 32 minutes by 2022, while the journey between Ballarat and Melbourne would drop to 45 minutes later in the decade. The upgrade works would span a decade, with Mr Guy promising it would provide 10,000 jobs.

He also vowed to pour money into track and signal upgrades as well investment into two fleets of new-generation trains. Major sections of tracks would need to be replaced for the trains to reach the speeds promised, while safety upgrades would also be required. Mr Guy vowed that about a fifth of the project’s budget would be spent during his government’s first term. Express trains from Bendigo could reach Melbourne in 70 minutes, while trip times from the city to Warrnambool and to Traralgon would be halved within a decade. A train journey to Shepparton would also be cut to less than two hours.

The regional rail project would be done in three stages over a decade. Loading Stage one, including Geelong timetable changes next year, would create more express services, cutting trip times from 58 to 50 minutes. Major track replacement works in Warrnambool, Bairnsdale and Swan Hill would commence towards the mid-2020s. Earlier this year, Premier Daniel Andrews pledged a $50 billion, underground suburban rail network would be built, linking every major rail line in Melbourne and the new airport rail, if the party was re-elected.

Billed as "the biggest public transport project in Australian history", the Suburban Rail Loop is expected to take almost 30 years to build and connect key train lines from Frankston to Werribee. Loading But opposition treasury spokesman Michael O'Brien has accused the government of putting up a "plan for the next election rather than a plan for the next generation". "They have no business case, no engineers' report and they won’t rule out more sky rail across Melbourne," he said at the time. "They refuse to say how many thousands of homes would be compulsorily acquired". The Victorian election will be held on November 24.