The ACT's Chief Minister is banking on the federal government paying for half of the multibillion-dollar light rail extension to Woden.
Andrew Barr has also defended the time it will take to extend the route to Commonwealth Park, disagreeing with idea the timeline would drive down support.
Mr Barr is confident Canberrans would appreciate the importance and difficulty of the project, disagreeing with the suggestion the lengthy construction timeline would drive down support.
"I think people understand complex infrastructure projects take time and that they would prefer us to under promise and over deliver rather than the other way around," Mr Barr said.
The territory signed a $577 million contract to extend light rail from the city centre to Commonwealth Park, with the Commonwealth picking up half the bill and a completion date set for January 2028.
The 1.7-kilometre extension will be completed and open more than 8.5 years after the opening of the first stage between Gungahlin and the city.
The government has not revealed a cost estimate for the complicated extension over Lake Burley Griffin and around Parliament House to Woden, but the opposition has claimed it could cost more than $4 billion.
Mr Barr said he was "not going to make reckless financial decisions" or make "reckless infrastructure promises that can't be delivered".
A spokeswoman for federal Infrastructure Minister Catherine King declined to comment, but Ms King has previously encouraged the territory to come forward to the Commonwealth to discuss funding when it had a firm proposal.
Ms King praised the ACT's handling of the light rail project when the contract for stage 2A was announced.
The Chief Minister said in an interview with The Canberra Times the story of light rail stage 2A, which will reach Commonwealth Park, was more than just a short section of track.
Some parliamentary triangle staff would have a "short walk over the bridge" to get to work, and a Commonwealth Park stop would be accessible for those who worked in Treasury, Finance or the National Library, Mr Barr said.
"We've already seen two significant land sales above the expected reserve. There's a number of other blocks on the market, or coming onto the market, and then we're progressing with the waterfront park [that is] funded," he said.
"I've got a process underway now about the City Hill park, and we'll look to make that a space that's more for humans than rabbits."
Mr Barr said the current federal government was supportive of the light rail project and had demonstrated its commitment to fund it.
"And the 50-50 funding model is the model that we will pursue," he said.
"Obviously, the first part of the funding for [stage] 2A was delivered under the Coalition government. And we see a more substantive contribution made by the current federal government.
"So stage 1, we delivered essentially on our own with a little bit of asset recycling - about a 10 per cent Commonwealth contribution. We've lifted that to 50 per cent.
"This is a pretty big initial down payment on the National Capital Investment Framework that the Prime Minister and I struck."
Mr Barr and the Prime Minister, Anthony Albanese, announced the framework to manage more collaborative infrastructure investment in July.
"The difference with this federal government is that the jointly funded ones they want to engage in are on our list, not projects that we've had no visibility on, which used to be the approach that [Zed] Seselja, the former senator, would bring," Mr Barr said.
"The first we hear about something we were meant to co-fund was on federal budget night? That doesn't happen anymore."
Mr Barr acknowledged criticism for talking about projects and then changing course, but said it was better to test whether they could actually be built.
"I've walked away, famously, from a particular location for the stadium because it just wasn't going to work. I copped a lot of heat for that," he said.
"But it doesn't mean we're abandoning the project. We're just recognising that the location is better somewhere else."
The ACT government has this year released updated infrastructure plans, with new advice to the community and construction sectors on when projects are expected to commence.
Mr Barr said for many of the people in Canberra who work in government, his government's approach to infrastructure planning ended up being "quite respected".
"Not everyone is, you know, a public sector advocate, public policy purists. So there will be others who will have a different view," he said.
"But, I mean, name me an issue where there's a unanimity of view in this community, let alone any other. We're confident the work we've done on the infrastructure program is robust."
