Victoria state has seen a spike in COVID-19 cases, recording almost 150 new infections over the past week as new clusters have emerged in Melbourne.

While the numbers remain small compared to global tallies, the outbreak has rattled Australia, which has been rolling back restrictions after successfully curbing the virus spread.

Defence Minister Linda Reynolds said Thursday that 1,000 troops would be rapidly deployed to Victoria "in the coming days".

Up to 850 Australian Defence Force personnel will help monitor returned international travellers being held in hotel quarantine while about 200 others will provide logistical and medical support to COVID-19 testing facilities, she added.

Military personnel are already manning the borders of states that are closed to outside visitors as well as providing planning support to health and emergency management services, including in Victoria.

However, the deployment of such a large military contingent to a major Australian city is unprecedented in the coronavirus crisis.

It comes as community concern about the virus spread ramps up in Melbourne, with pop-up testing centres set up in virus "hot spots" in response to long queues and supermarkets reimposing buying limits amid fears of a return of panic-buying.

Virus clusters have emerged in large family groups spread across the country's second city, at a hotel used for quarantining returned travellers and at a clothing store.

Australia has recorded roughly 7,500 cases of coronavirus and 103 deaths in a population of 25 million, with several regions believed to be effectively virus free.