COVID-19: Australia's New South Wales reports three more community coronavirus cases

The New Zealand Government says it's monitoring developments in Australia after the state of New South Wales (NSW) reported two more community COVID-19 cases.

Six new cases have been found in the community in the past 24 hours, leaving local health officials scrambling.

Three new cases were reported at Sydney's Northern Beaches on Thursday - just a day after another three, including an airport worker, tested positive for the disease - the country's first community cases in two weeks.

Jason Falinski, an MP based on the Northern Beaches, confirmed one of the cases worked at a retirement village. NSW Health Minister Brad Hazzard said on Thursday afternoon that worker's partner has now also tested positive, bringing Sydney's active community case total to six - five in the Northern Beaches plus the airport worker.

The Northern Beaches cases currently have no known links to the border and the sources of infection are unknown.

"Urgent investigation and contact tracing is ongoing into all locally acquired cases," NSW Health said in a statement.

Australia had largely contained community transmission of the coronavirus. Before Wednesday's airport worker infection, the country last reported a local case on December 3 when a hotel quarantine worker in Sydney tested positive for the virus.

The cases raise fresh questions over a potential trans-Tasman travel bubble, with the New Zealand Government saying one would only proceed should Australia go 28 days without a local case.

A spokesperson for COVID-19 Response Minister Chris Hipkins told Newshub the Government would be monitoring the latest developments closely.

Prime Minister Jacinda Ardern announced earlier this week the bubble could be in place from the first quarter of 2021, but only if there was no change to each country's COVID-19 situation.