There are now 21 community cases linked to the highly infectious Delta virus strain with 10 new cases reported on Tuesday in New South Wales.
Passengers on two flights which travelled between Sydney and Wellington have been identified as close contacts.
It includes Qantas flight QF163 which departed Sydney just after 7pm last Friday and arrived in Wellington on Saturday at about 12am.
Air New Zealand flight NZ247 which flew out from Wellington at 10am on Monday and arrived in Sydney at 11.30am has also been flagged.
New South Wales Health issued the alert - and has asked everyone on the flights to get tested and isolated for 14-days.
Updated advice for travellers from NSW
NZ health officials have updated their advice to anyone now in this country who had recently visited Sydney's Westfield Bondi Junction mall.
One of the new cases reported on Tuesday is connected to the busy mall which is popular with Kiwi tourists.
"In line with NSW Health's advice: anyone in New Zealand who was at Westfield Bondi Junction (including the car park) in Sydney's Bondi Junction at any time between 12 June and 18 June should contact Healthline on 0800 358 5453, get tested and stay at home until they get a negative test result, or remain isolated if instructed."
Anyone who has been in Sydney since June 11 is asked to check the NSH Health website.
In New South Wales all but one of Tuesday's new Covid cases have been linked to the highly infectious Delta virus strain.
All bar one of the new cases is linked to existing cases.
The mystery case is a Year 3 student who attends a school in Waverley, the Sydney Morning Herald reported.
New Zealand contact tracing teams last week got in touch with 6824 passengers from New South Wales, who arrived in the country before last Wednesday, when the first recent community case in Sydney was announced.
These were travellers who had been in NSW since June 11.
There are 16 contacts related to locations of interest in Sydney that are currently in New Zealand.
The majority of these contacts identified themselves by calling Healthline - and have been advised to get tested and stay home, the Ministry of Health said.
Five of the 16 are required to isolate for 14 days and get tested twice in that time and all have returned a negative first test result.
The remaining 11 are required to self-isolate until they return a negative test, of which eight have done so, while three results are outstanding.
Meanwhile, the quarantine-free travel pause with Victoria lifted last night at 11.59pm as New Zealand health officials deem the risk to the public as low.
There have been no new local cases in the past 24 hours as the Garden State brings its latest outbreak under control.
Queensland health officials also announced a new community case on Sunday, in an air crew worker.
However, New Zealand health officials had determined that, at this time, the Covid public health risk to New Zealand was low.
There were no new cases of Covid-19 in the community or in managed isolation reported on Tuesday in New Zealand.
The Ministry of Health said two previously reported cases had recovered with the number of active cases in the country sitting at 20.
The seven day rolling average for new cases found at the border is one.
