UPDATE 3.20PM: Auckland will heading to level 1, Cabinet has decided.

The decision was made on the advice of Director-General of Health Dr Ashley Bloomfield.

In her media standup today, Prime Minister Jacinda Ardern said the change will be from midnight today.

She says face coverings will be mandatory on public transport throughout the country at alert level 1.

Masking is already mandatory in Auckland on public transport. Keeping it mandatory throughout the country at level 1 is new.

The order will be kept under review as vaccines are being rolled out.

Ardern asking people to "please" use the Covid-19 tracer app.

While scanning is currently not mandatory, it's been said previously that this is something Cabinet will be considering

EARLIER:

One new case of Covid-19 in the community has been announced as Auckland waits to find out if it will join the rest of the country in alert level 1.

The new case is linked to the existing community cases and is already in quarantine, the Ministry of Health says.

There are six new cases in managed isolation, four of which are historical.

Prime Minister Jacinda Ardern will make an announcement about any alert level shift later in the afternoon, but it is expected Auckland will soon be returning to level 1.

Ardern earlier said she was confident the alert levels would be changed unless something "significant" emerged in the morning's testing results.

The Government's confident a ring had been placed around this community cluster, she said.

The alert changes were sparked by a group of community cases of Covid-19 within a family that had an indirect link to the border.

Linked to that through a contact at Papatoetoe High School were four further cases.

Today's case is part of the same household. They had previously been tested and returned a negative result, and had been self-isolating.

They have been in quarantine since Friday as a precaution, the ministry says.

Given the contact tracing already carried out in relation to this family, as well as the fact the person has been isolation, the ministry said the public health risk is considered "very low".

Out of the 125 close contacts associated with all the cases in this cluster, just two test results are still pending.

As of Monday morning, a total of 31 close contacts and 1416 casual plus contacts have been identified at Papatoetoe High School – an increase of three casual plus contacts.

Four teachers and 28 students will remain away from school while they have a second test.

Close contacts who have been in isolation since being tested will be able to return to school from Wednesday.

There's still a question mark over where the February cluster sprung from. Further testing of the Auckland Airport precinct, where one of the first cases works, is still considered the most likely source – but further testing hasn't given any clues as to how transmission might have happened.

A link to the Four Points Sheraton MIQ facility is still being probed, but it is considered an unlikely source of infection.

The six new cases in managed isolation arrived from the United States, Iraq, Morocco and Colombia and have been moved to quarantine facilities in Auckland and Christchurch.

If Auckland shifts down levels, there may be additional restrictions at level 1.

Ardern has said Cabinet will consider making mask use on public transport permanent throughout New Zealand and could make signing in with the Covid app, or with a pen and paper, compulsory.

-Stuff/ Josephine Franks.