Victoria's quarantine facility proposal is "fair dinkum" and comprehensive, according to the prime minister.
While Scott Morrison stresses the federal government has not made a decision on the plan, he has welcomed the Victorian government's idea.
It is in stark contrast with last week, when Defence Minister Peter Dutton initially derided the proposal as "smoke and mirrors".
"The proposal has been put to us, I take (it) as a very serious and well-considered and comprehensive proposal," Mr Morrison told 3AW radio.
"We will consider these things - what I do welcome that this is a very comprehensive proposal ... we will look at it carefully.
"It's being assessed by the home affairs department ... I do think it's a fair dinkum proposal."
The proposed 500-bed centre at Mickleham on Melbourne's northern fringe, announced by the state government last Thursday, needs $200 million in federal funds, with the state chipping in $15 million for design and planning.
Under the Victorian proposal, the new facility would be operating by the end of the year.
The state government would operate and manage the facility, a point also noted on Thursday by the prime minister.
"That's a very good move, because it understands that they are enforcing a Victorian state government public health order," he said.
Acting Premier James Merlino welcomed Mr Morrison's comments.
"I was really pleased as I said yesterday to parliament, the prime minister's response that he's taking the proposal seriously, that it's a comprehensive proposal, and it's been looked at in good faith," he said.
"Hotel quarantine is not a fit-for-purpose model, it's the best model we had at the time but it's not fit for purpose and that's why we're advocating to the Commonwealth for an alternate quarantine hub."
Also on Thursday, Victoria announced it was sending 1000 ventilators to India as the country reels from its coronavirus surge.
On Wednesday, India became the second country to reach the grim milestone of 20 million COVID-19 infections, with hospitals running out of beds and oxygen.
The aid package, which will include supporting equipment such as connectors and humidifiers, will be worth more than $41 million.
"The situation in India right now is devastating and shows that the fight against this pandemic is not over - we have a responsibility to help where we can," Mr Merlino said in a statement.
The state government said the donation to the Commonwealth medical stockpile would come from a health department stock of 4000 ventilators in storage.
"Thanks to strong stocks here in Victoria, we are able to donate these ventilators to India and provide crucial support to thousands of people in India," Health Minister Martin Foley said.
The donation comes as Victoria health authorities went on alert following a mystery local case in NSW.
On Wednesday night, Victorian health authorities said they would contact people who have travelled from NSW since April 30.
Any Victorian who has visited the NSW exposure sites must have a test, isolate and quarantine for 14 days.
The dates for the exposure sites, listed on the NSW Health website, range from last Friday through to Tuesday.
Victoria has recorded its 69th consecutive day without a locally acquired case of COVID-19 on Thursday. There were two cases in hotel quarantine.
The state's vaccination hubs immunised 8163 people, down slightly from Tuesday's record of 8406.
Australian Associated Press