Prime Minister Jacinda Ardern has announced that New Zealand will remain at the current alert levels for another 12 days.

Arden and Director General of Health Ashley Bloomfield revealed the lockdown decision from the Beehive this evening.

Auckland will remain at alert level three for another 12 days, with the rest of New Zealand staying at alert level two during this time.

'Auckland will remain at level 3 and New Zealand will remain at level 2 until 11.59pm on Wednesday Aug 26,” Ardern says.

This decision will be reviewed on August 21.

She hopes by this time the perimeter of the cluster will be identified and isolated.

At this stage there is nothing to suggest we need to move to a level 4 lockdown, she says.

Ardern says construction will continue and hospitality services will continue under the existing level 3 operating protocols.

"Cabinet also does not want Auckland to be in level 3 any longer than is needed to ensure the outbreak is contained.

"The best economic response is a strong health response."

She says elimination remained the country's overall covid strategy.

"Together we have got rid of Covid before. We have been world leading in our Covid response. We can do all of that again. 1.4 million New Zealanders are carrying a heavy load for our team of 5 million right now.

"Here's what I ask today. If you're in Auckland, stay at home in your bubble. Wear a face covering if you can."

It was important to remember that level 2 would allow for more economic activity than level 4, Ardern says.

"We will use what tools we have to protect jobs, incomes and businesses as well as people's health."

She says the wage subsidy scheme will be extended nation-wide until the end of the level three restrictions.

Details will be finalised over the weekend.

The government is attempting to get things back on track after the 102 days without community transmission came to an abrupt end on Tuesday. In less than 24 hours Auckland was in level 3 lockdown and the rest of the country had moved to level 2.

The prime minister says today there were signs the latest cluster has been found "early in its life".

The earliest case to date is a worker at Americold who first become sick on 31 July.

"It's the earliest sign of the re-emergence."

The source was still not clear, Ardern says, but genome sequencing "suggests it is not a case of the virus being dormant or of a burning ember in our community, it appears to be new to New Zealand".

There has been 12 new confirmed cases and one probable case of COVID-19 reported in New Zealand today.

Two of the confirmed cases are from Tokoroa and are close contacts of a family member which is part of the Auckland cluster.

There are 12 cases linked to the existing cluster.

Ashley says a 13th case, which is currently in Auckland Hospital, has no known link and an investigation is underway to find out where this person contracted the virus.

"All confirmed cases have been transferred to the quarantine facility in Auckland."

He says there will be community testing facility operating in Tokoroa in the weekend.

The new confirmed cases bring New Zealand's total number of cases to 1251. This is the number that will be reported to the WHO.

There is now 48 active cases in New Zealand - 30 of this are linked to the community outbreak in Auckland.

"It is important to remember that the problem is the virus. People are the solution. There is no blame or stigma for people who have the virus," Ashley says.

-Additional reporting RNZ