Prime Minister Jacinda Ardern has confirmed New Zealand south of Auckland will move to alert level 3 from 11.59pm tomorrow night.
Level 3 would be in place for a week before it was reviewed, Ardern said.
Business owners and operators who ran businesses allowed to operate at level 3 were able to return to their workplaces to set-up for operating at the reduced alert level.
There had been no evidence that would cause Cabinet to change its mind, she said.
"Wider waste water testing in Christchurch has not shown up any further postive results meaning the positive results last week we believe can be most likely attibuted to cases in managed isolation facilities in the city."
Auckland will stay in alert level 4 for at least two more weeks - until Tuesday September 14, Ardern confirmed.
Wastewater testing in Northland is due on Thursday. If the tests are all clear, Northland will go to level three at 11:59pm on Thursday.
"My final message is for all of those outside of Auckland. Please remember that level 3 does not mean freedom.
"It means caution, it means staying in your bubble, it means distance, it means contactless transactions."
The PM presented a graph which indicated what would have happened if we hadn't moved quickly into lockdown, with cases "literally off the charts", totalling 550 per day.
"The more we do to limit our contact, the faster we exit these restrictions."
Ardern cited evidence offshore where countries were battling large hospitalisation rates.
She said today's numbers showed level four was making a difference, with cases decreasing outside of households.
But, she said, "we need to be confident any cases we may have are contained and isolated".
Everyone in Auckland knew we are not there yet, Ardern said.
She said Auckland was doing a huge service, which has maintained the gateway to the world and has worked hard to keep Kiwis safe during an outbreak.
It was too soon to say whether New Zealand had reached the outbreak's peak, Ardern said.
"Whether or not we have plateaued ... I do think we need more time."
53 new community cases
It comes as 53 cases, all in Auckland, were announced on Monday. After highs of 82 and 83 in the preceding days, the drop is the strongest indication yet the lockdown in place since August 18 is having an impact.
Director-General of Health Dr Ashley Bloomfield described today's data as encouraging.
He said of yesterday's 83 cases, 72 per cent didn't create any new exposure events. Of yesterday's cases, only 28 per cent were considered to be infectious in the community.
Bloomfield said the R value was now under 1, which was a good sign.
One hundred and one essential workers were cases, but many were from earlier in the outbreak, Bloomfield said. Four were infectious in their workplace and seven had been infected in their workplace.
Thirty-seven cases are now in hospital. Of those, five cases are in stable condition in the intensive care unit.
On the passport vaccination issue, Bloomfield confirmed it was not necessary to show a passport for a jab. However, he explained the process of accessing an NHI number can be expedited by showing documentation. He was assured no particular group of people was being targeted in this way.
"Everybody in the programme is very aware ... that no one is required to show identification."
Ardern said the only requirement to get a jab was to physically be in New Zealand.
She said she wasn't aware of it happening before.
On quarantine capacity, Ardern said the backlog had been cleared and people were moving into one of two new facilities which had been onboarded.
Her understanding was that all cases were moving into MIQ.
Vaccination rollout
Close to 47,900 Covid vaccines were administered yesterday - a record for a Sunday. Over 50 per cent of the eligible population has received at least one vaccine dose.
Of the 3.33 million doses of the vaccine administered to date, 2.17 million are first doses and 1.16 million are second doses.
Ardern said rates of vaccinations would be looked at during the week to see how long current levels could be maintained while having enough in stock.
Over 300,000 doses had been delivered weekly and Ardern said she was working on whether NZ could "move beyond that".
Asked whether vaccines were being diverted from other regions for Auckland, Ardern said there wasn't a need as demand had been met.
The current approach was being reviewed to make sure bookings were maintained and demand was met, especially in Auckland.
For rest home vaccinations or people being cared for at home, Ardern said some thought had been put in. Rest homes had been visited by vaccinators through their local DHBs and most rest homes had been offered vaccinations.
Those with disabilities and people being cared for at home had been provided for in a way that best suited them, including through vaccination clinics that operated in a low-sensory environment.
Death linked to Pfizer vaccine
Meanwhile, a woman has died after developing myocarditis, a rare side effect of the Pfizer Covid vaccine.
The Ministry of Health said this was the first case in New Zealand where a death in the days following vaccination has been linked to the Pfizer vaccine.
The Ministry says the Covid-19 Vaccine Independent Safety Monitoring Board advised officials to ensure that healthcare professionals and consumers remained vigilant and were aware of the signs of myocarditis and pericarditis following her death.
"The CV-ISMB considered that the myocarditis was probably due to vaccination. The CV-ISMB noted that there were other medical issues occurring at the same time which may have influenced the outcome following vaccination," said the Ministry in a statement.
The woman's death had been referred to the Coroner and the cause of death had not yet been determined, said the Ministry.
Asked about vaccine hesitancy in light of the vaccine-related death, Bloomfield recognised it would be a worry for some, but reassured people that there was plenty of evidence the vaccine was safe and myocarditis was very rare.
While the Centre for Adverse Reactions Monitoring had received other reports of deaths in someone recently vaccinated, none were considered related to vaccination.
The Ministry said the benefits of vaccination using the Pfizer brand continued to greatly outweigh the risk of both Covid infection and vaccine side effects, including myocarditis.
