Kiwis will find out at 4pm tomorrow whether the country will come out of lockdown and move to level 3.

Prime Minister Jacinda Ardern made the announcement at this afternoon's daily coronavirus update, accompanied by Director General of Health Ashley Bloomfield.

When asked if we were likely to stay in level 4 for another week until contact tracing is at gold standard, Arden said "we are not going to get into hypotheticals".

Bloomfield said there had been nine new coronavirus cases in New Zealand and one new death.

The death brings the total toll to 12 and is of a man in Invercargill at home who was linked to the Bluff wedding cluster. It is believed to be the first coronavirus-related death not in hospital.

Bloomfield said there were only six recent cases where the source of infection was unknown - including one in Whanganui and one in Timaru - and targeted community testing had already been carried out in Timaru to gauge the prevalence of Covid-19 in that community. Ongoing discussions were also taking place in Whangaui, where more testing was recently done in response to low per capita testing in that region.

The new cases are made up of four confirmed cases and five probable cases.

They are all linked to confirmed cases.

The total of confirmed and probable cases in New Zealand is now 1431.

There are 18 people in hospital, including three in ICU and two in a critical conditions.

There were 4146 tests processed yesterday, bringing the total of tests conducted to 83,224.

Bloomfield said 442 tests took place in Auckland yesterday, and with three-quarters of the results known, none have so face tested positive.

He said there were 131 healthcare workers had Covid-19, half of them having contracted the virus in the workplace.

Coming out of lockdown

Arden said Cabinet was meeting at 10.30am tomorrow and a decision on whether New Zealand will come out of lockdown would be announced to the public at 4pm.

She said a move to level 3 would not be a return to pre-Covid life, and the ongoing battle was a long-term one.

She added that returning to a normal social life would potentially allow the virus the spread.

New Zealanders had stayed home and saved lives, and Google data backed that up by showing fewer visits to beaches and parks, Ardern said.

"I know it hasn't been easy but it has been working."

Criteria on which to base the decision to come out of lockdown included testing and contact tracing capacity, community transmission, border restrictions, and the capacity of the health system.

Economy and public attitudes, businesses' ability to comply with restrictions, and the Government's ability to enforce those restrictions would also be looked at.

The Government's decisions had been based on public health and that had also been the best way to protect the economic fallout, she said.

Businesses should be assessing whether they can operate at level 3.

Ardern said the decision to move into the lockdown was the right one, and she thanked small businesses because no one underestimated how hard it has been for them during the lockdown.

She made two pleas to New Zealanders: "If you even have a sniffle or a sore throat, get a test.

"And record you movements as if we may come and interview you tomorrow to find out who you've been with."

It was helpful for people to keep a written record of who they have been with and their movements, as that would help contact tracing and moving down alert levels.

Bloomfield said the Ministry of Health's contact tracing system was "not particularly easy" to get information out of, and it was being updated "at pace" and might be at a gold standard within a week.

He said the Ministry wanted to be able to reach 80 per cent of close contacts within three days information being analysed, which was being worked on this weekend.

Ardern said not to read too much into the statement that the gold standard was not in place at the moment.

Bloomfield said Dr Ayesha Verrall's report into the Ministry's contact tracing ability would be released tomorrow after Cabinet's decision was made.

Ardern added that smartphone technology would be part of the contact tracing solution, but it didn't need to be in place for the lockdown to be lifted.

Bloomfield said the number of tests, the results of community testing and the positivity rates were all good signs but it was up to Cabinet to make a decision about the prevalence of community transmission.

Hunting for the source

Bloomfield said there were only six recent cases where the source of infection was unknown - including one in Whanganui and one in Timaru.

Thorough tracing of contacts and workplaces were being undertaken by the public health units in those areas.

Targeted community testing had already been carried out in Timaru to gauge the prevalence of Covid-19 in that community.

Ongoing discussions were also taking place in Whanganui, where more testing was recently done in response to low per capita testing in that region.

Bloomfield said a robust response was in place for a mental health staffer who had contracted Covid-19 at Tauranga Hospital.

He said he was confident in DHBs' infection prevention systems, but nothing was fail-safe.

Ardern said that hospital resources had been managing so far.

There were 1601 people in managed isolation because of strict border controls, some of which were in strict quarantine.

Lockdown breaches

Ardern said there were 371 lockdown breaches in the past 24 hours up to 8pm last night.

She said it was hard to get a true sense of lockdown compliance with the variations in frequency of police patrols, but Google data showed that compliance was very high.

"New Zealand has done exceptionally well."