Premier Jacinta Allan was grilled on Melbourne's Suburban Rail Loop in a heated 40-minute press conference on Thursday after the federal government made good on a $2.2 billion funding commitment.
She welcomed the release of funding but confirmed there were strings attached, including land acquisition, utilities and ground conditions.
The planned 90km orbital rail line is designed to run from Cheltenham in Melbourne's southeast to Werribee in the outer west via the airport at Tullamarine.
Cash-strapped Victoria is counting on the Australian government to stump up a third of the $34.5 billion project's estimated cost for the first stage between Cheltenham and Box Hill.
So far the Victorian government has committed $11.8 billion, with the remaining third expected to come from "value capture".
That is taxes, charges and fees generated through increased land value and developments near station precincts.
Ms Allan was repeatedly asked what year value-capture cash would start flowing into state coffers and when the first house associated with the project would be built, but she could not say.
After almost 20 questions on the rail loop, a journalist wanted to return to the topic but the premier walked away.
"We're done," she told reporters.
Anthony Albanese pledged $2.2 billion to the mega project prior to the 2022 federal election in what was billed as an "initial" investment.
Almost three years later, Federal Transport Minister Catherine King on Wednesday confirmed the $2.2 billion had been released following assessments by her department and Infrastructure Australia.
The federal government is refusing to guarantee any more funding, with Infrastructure Australia working with Victoria on its project evaluation report.
"There are still some hurdles that the Victorian government will need to overcome in relation to advice that I will receive from Infrastructure Australia about, particularly the costings around value capture before the Commonwealth can make another investment," Ms King said.
"I'm a supporter of it, but I also need to make sure that I'm getting value for money for Australian taxpayers' dollars."
Ms Allan had been "shamed" by the federal government's failure to commit its share of requested funding and the project must be paused, opposition major projects spokesman Evan Mulholland said.
"Our credit rating agencies have warned of a ratings downgrade without additional federal funding, and this reckless spending is pushing Victoria deeper into debt," he said.
"If Jacinta Allan says she's listening after the Werribee by-election, she's certainly not showing any signs of it."
The entire project was initially estimated to cost $50 billion when first announced by Labor before the 2018 state election.
The state's independent Parliamentary Budget Office cast doubt on that estimate in a 2024 update, putting the cost to build the first two sections at $96.4 billion.