Ardern says to date, 29 cases associated with the Omicron cluster have been identified. All are in isolation, but the government is yet to establish firm links to a known border case.

She says with Omicron the source of the outbreak may never be known.

Some testing sites in Wellington and Auckland are switching to drive-through to increase capacity.

Ardern asks everyone who is eligible to get their booster as soon as possible. She says over 73 percent of eligible people over 65 have now been boosted, and every DHB is on track to complete booster programmes in aged care facilities within the next week.

Mask use

Ardern says Cabinet has agreed to enhance mask-wearing protocols.

She says under the red setting, masks must now be worn at food and drink businesses, close proximity businesses, events and gatherings. The same exception for when people are eating, drinking or exercising still apply.

She says the changes also do not apply to non-public facing workplaces, swimming pools, and gatherings where you have the exclusive use of the premises.

Face coverings must now also be "an actual mask", she says.

"That means no more scarves, bandanas, or as some of us may have seen from time to time, t-shirts pulled up over the face, for example."

All workers legally mandated to be vaccinated must also now wear a medical-grade mask, for example type 2R or level 2 mask or above, while working in public-facing roles. This includes the widely available blue medical grade disposable masks.

School students Year 4 and up are already required to wear a mask. For consistency they will now need to wear a mask while on Ministry of Education-funded school transport services and public transport.

Ardern says the science has been updated and these changes will help save lives and give time to get more of the population boosted.

Testing

Bloomfield says another 14.5 million rapid antigen tests will arrive in the country by the end of February.

In a statement, Associate Minister of Health Dr Ayesha Verrall said the government had doubled the varieties of RATs for import and supply in New Zealand.

Registered New Zealand businesses would also be able to import, supply, distribute or sell the approved test without having to use an authorised importer, she said, and the process for approving new RAT types was made easier.

She said significant progress was being made on New Zealand's testing systems after a review of testing by the technical advisory group led by Professor David Murdoch in October.

New Zealand's capacity for PCR lab testing had increased from 39,000 tests per day to 58,000 per day, and up to 77,600 per day with surge capacity for up to seven days, she said.

"We have continued to adapt our public health response to safeguard the health and wellbeing of all New Zealanders throughout this pandemic," Dr Verrall said.

"Our labs have already processed 5,906,843 tests to date and our highest testing day so far was 24 August 2021 where 49,736 tests were completed."

She said a rapid rise in case numbers due to Omicron would require a shift away from testing everyone, to targeting testing at those most at risk or needed for critical infrastructure.

This was in part due to automation of some testing tasks, including with a de-capping robot designed by that could remove and replace the caps from sample tubes.

The robots were designed in partnership between Canterbury DHB's Medical Physics and Bioengineering team and local engineering company Design Energy.

Today the Ministry of Health reported 25 new cases of Covid-19 in the community, including 10 confirmed new Omicron cases.

Earlier Education and Covid-19 Response Minister Chris Hipkins announced the government is ordering 5000 portable air cleaners, to ensure schools are ventilated enough to help prevent the spread of Covid-19.