Auckland will stay at Alert Level 3 and the rest of the country at Alert Level 2 for 12 more days, until 11.59pm August 26, Prime Minister Jacinda Ardern announced today.
Ms Ardern said this would be reviewed on August 21 and the wage subsidy scheme would be extended.
"We will overcome an obstacle we knew would come out way," Ms Ardern said.
Director General of Health Ashley Bloomfield said the total time of 14 days at Level 2 and 3 would give them sufficient time to find the extent of the spread.
Ms Ardern said in the event of the country having to move to Alert Level 4, the criteria was multiple outbreaks and community transmission - "a much larger scale that what we’re seeing here".
"Cabinet also does not want Auckland to be in Level 3 any longer than is needed to ensure the outbreak is managed."
She also revealed there are 29 cases that have been identified as having links to the community-based cluster in Auckland and one more that is likely to be linked but is still being investigated.
Two of those cases were confirmed to be in Tokoroa.
The community-based infection appears to be new to New Zealand, Ms Ardern told media today.
"Although we haven't yet found that source, we will continue looking very, very hard for the lack of a current link."
The earliest case to date was from a worker at Americold who became sick on July 31.
"This may not yet be the origin," Ms Ardern said. "There is still no clear connection as this point."
Genome testing had not found a link to border or managed isolation facilities. Ms Ardern said the theory that it was a strain of Covid lying dormant in the community had largely been distinguished.
She said they would continue to look into the coolstore, including testing surfaces.
"We do not necessarily need to answer that question to contain and deal with this cluster effectively," Ms Ardern said in answering if the importance of the original source.
Auckland has been at Alert Level 3 and the rest of the country has been at Alert Level 2 since noon Wednesday, restrictions which were due to end at midnight tonight.
Today the Director-General of Health announced there were 13 new Covid-19 cases in the community in New Zealand, linked to the original community-based cases in Auckland.
One person was in hospital and the link had not yet been established - however Dr Bloomfield said this was due to the positive result having come back very recently.
The Ministry of Health has now confirmed the country currently has 49 active cases of Covid-19.