The Victorian government's contentious Suburban Rail Loop "cannot be stopped" as a cloud hangs over the rollout of its new public transport ticket system.
Global consortium Terra Verde has been awarded a $1.7 billion tunnelling contract for the $34.5 billion eastern section of the rail line.
The deal is to build 10km twin tunnels between Glen Waverley and Box Hill, with another consortium already signing a $3.6 billion deal to tunnel the rest of the 26km stretch from Cheltenham.
The Labor state government said the latest tunnelling deal came in under what was initially budgeted but Premier Jacinta Allan did not say by how much.
"It demonstrates there is huge competitive interest from these global construction companies," Ms Allan told reporters on Sunday.
The entire 90km orbital rail line is designed to run from Cheltenham to Werribee via Melbourne Airport.
Boring on the first phase of the loop is expected to begin in 2026, with completion slated for 2035.
Some businesses to be forcibly acquired were granted a request for an extra nine months to vacate but Ms Allan was adamant it wouldn't delay the project.
"It's absolutely tracking on time and on budget," she said.
Transport Infrastructure Minister Danny Pearson said there was "simply no stopping" the project as early works power ahead at at all six station sites.
"You can't stop this project," he said.
Victoria has pledged $11.8 billion to build the eastern section, with a third of funding expected to come from the federal government and the rest from unexplained "value capture" revenue.
The Albanese government has only committed $2.2 billion for the project so far, leaving a $20 billion funding hole.
The entire project was initially estimated to cost up to $50 billion in 2018, before its 2021 official business case showed the east and north sections could cost between $30.7 billion and $57.6 billion.
The state's independent Parliamentary Budget Office cast doubt on that estimate, putting the cost to build the first two sections at $125 billion.
The coalition wants construction paused, with Opposition Leader John Pesutto scolding the premier for signing billion-dollar contracts without the project's funding fully guaranteed.
"It can be stopped, it should be stopped, it must be stopped for the benefit of current generations of Victorians but also future generations," he said.
Ms Allan also swatted away questions over a reported legal stand-off with Conduent, the New Jersey-based company it picked to overhaul and operate Victoria's outdated myki system.
Conduent wants extra funds to deal with technical issues after it signed a 15-year deal worth $1.7 billon in December 2023, The Age reports.
The premier suggested Conduent was on track to trial fare payments made by credit card, iPhone and even some smart watches by the end of 2024 and said the department was "working closely" with the company.
"They are working incredibly hard on this complex technology project," she said.
"Those reports of the company walking away are simply incorrect."
