Victoria is shut off from the rest of the country as a record number of COVID-19 cases prompted NSW to shut their border.
NSW had been the last state to allow an open border with Victoria, which reached a grim milestone on July 6, including two new deaths in 24 hours.
The 127 new cases of coronavirus is a record daily increase for Victoria.
A 90-year-old man died in hospital on Sunday night and a man in his 60s died on Monday morning, bringing the national pandemic death toll to 106.
Victoria has had 20 consecutive days of double-digit new cases, in stark contrast to the rest of the country.
Victoria now has 650 active cases, an increase of 590 in four weeks, while other states have remained stable.
Premier Daniel Andrews confirmed the border will close at 11:59pm on Tuesday following crisis talks with NSW Premier Gladys Berejiklian and Prime Minister Scott Morrison.
“We have, all of us, agreed that the best thing to do is to close the border,” Andrews told reporters on Monday.
Andrews said the border closure means staff at airports and train stations can be redeployed into “much more important roles”.
He said stood-down Qantas staff have been called up to work in the hotel quarantine program in Victoria, reporting directly to the Department of Justice.
More than 100 additional personnel from the Australian Defence Force will also be called in to help.
Chief Health Officer Sutton Brett Sutton said the number of known cases in the nine locked-down public housing towers at Flemington and North Melbourne has almost doubled since yesterday, from 27 to 53.
More than 3000 meals and 500 hampers of food were distributed to residents in the towers on Sunday, while about 350 personal care packs, including soap, deodorant, toothpaste, nappies and baby formula have been handed out on Monday morning, as well as bread and milk.
Increases of 20-30 community transmission cases per day were recorded last week.
Andrews said the rising number of new cases is challenging.
Benita Kolovos in Melbourne