Minister of Health Chris Hipkins has poured cold water on the Deputy Prime Minister's suggestion the new cluster of COVID-19 cases came from a breach at a border quarantine facility.
But both he and Winston Peters are warning Aucklanders to prepare for an extension to the level 3 lockdown restrictions to be announced on Friday afternoon, though no decision had been made as of the morning.
Peters told Australia's ABC 24 News on Thursday evening a "usually very reliable" journalist told him the city's outbreak was linked to the quarantine system, where Kiwis arriving home from overseas are placed if they're showing symptoms or test positive for the virus.
"I think, when that comes out very shortly, in a matter of maybe less than a day, we'll find out that was the case. But you don't always find out from your officials," Peters said.
"You don't always find out from the experts. It's something you sort of find out by contact with other people."
The Prime Minister's Office quickly said it had no evidence of any connection, and on Friday morning Hipkins said that remained the case. The last update he had at 10:30pm on Thursday said no link between the border facilities, anyone who works there or anyone with recent overseas travel history had been found.
"That is obviously the missing piece of the puzzle that we're working as hard as we possibly can to try and find."
Infected people can take several days to start showing symptoms, and the virus can travel asymptomatically too - leading some experts to believe it might have been circulating undetected for weeks.
Hipkins said there's no evidence for that yet either.
"All of the positive cases we've had to date - and there will be some more announced at lunchtime today, at one o'clock today - all of them relate to the same single cluster. They all relate to one another. All of the testing we've done up and down the country has not identified any other cases of COVID that aren't related to this one. What we still don't know however is how this cluster came into being in the first place."
Hipkins said the new cases to be announced at 1pm so far don't amount to a "heap", but new information is constantly trickling in - and that's why the Government will be leaving any decision on an extension to the lockdown in Auckland until Friday evening.
Peters told Australia's Nine on Thursday the Government is treating the situation as a "worst-case scenario", and Hipkins used similar language.
"We've been saying now for several months, since our level 2 last time ended, that people should always be prepared for the worst. We want people to be ready, to take action and respond as we need them to.
"This is a virus - it's unpredictable. We don't quite know what's going to happen, but we will know more this afternoon once we get all the overnight testing results in and the contact tracing from this cluster in during the course of today. We'll know a lot more to make a much more informed decision than we know now."
National Party MP Simon Bridges, who chaired the Epidemic Response Committee during the first lockdown, told The AM Show he expects Auckland's lockdown to continue.
"We have a Prime Minister who's shown she's very cautious and conservative on these issues. If I had to make a guess I would say we would stay in level 3. I would simply say to Chris and his team, you know what, if you were going to level 4 you would want a very clear, strong, robust case around that.
"And also heed the advice of the likes of Michael Barnett of the Auckland Chamber [of Commerce] - learn the lessons of last time so we can be pragmatic around things like greengrocers, butchers and many other businesses who can safely operate... I would really hope there's been some lessons learned from the last lockdown."
Hipkins said with every new case so far linked back to the same cluster, there would be no justification for going to level 4.
"Level 3 is certainly the maximum level you could justify based on the information we know now. If we started to see other clusters, or other unrelated cases, that would change things."
He said Bridges' characterisation of the Government's response as cautious was correct.
"One of the lessons from other countries including our neighbours across the ditch is if you're slow to respond in the early stages of an outbreak, that's where it gets away on you. So we've been very hard and very fast again - that gives us our best chance."
The Government will reveal Auckland's lockdown future at 5:30pm.