Cabinet yesterday decided against easing Auckland's lockdown restrictions early but the Prime Minister is sounding optimistic about the chances of the city moving back into level 2 next week.
"We have made good progress," Ardern said yesterday, adding that Auckland got in front of the virus before its spread really took off.
She said there is cause for "all New Zealanders to feel optimistic" at just how successful the country's Covid-19 resurgent plan has worked so far.
More good news was the fact a Covid-19 positive person, who worked at St Lukes mall, has been linked back to the Auckland cluster.
Despite this, Ardern said that yesterday was not the day to deviate from the current Covid-19 containment path.
"We need to stay the course," she said, before adding that there was "certainly nothing to suggest we need to escalate our response".
That course, according to Ardern, is for Auckland to come out of level 3 at 11.59pm on Wednesday next week.
But that timetable might yet be derailed, given news that five of the nine new Auckland cluster Covid-19 cases yesterday were linked to five different churches in South Auckland.
Director general of health Ashley Bloomfield said there were 223 possible contacts from the identified cluster-linked Pasifika churches.
So far, 170 have been tested – the results are pending, Bloomfield said.
Infectious disease expert, and Otago University professor, Michael Baker said churches are "high risk" Covid-19 spreading situations, especially if they are indoors.
This is because of the usual lack of physical distancing and higher than usual level of person-to-person contact.
Around the world, churches have been labelled super-spreader events and, in some instances, have led to an explosion of cases.
"There has always been great concern about church services," Baker said.
The results of the more than 220 church tests will be closely dissected by Ardern and the rest of her cabinet on Monday.
Ministers will also be looking closely at the results of testing this weekend, as well as the effectiveness of the contact tracing system.
But at this stage, Ardern suggested things were looking good.
"There are encouraging signs we have the Auckland cluster circled."
She pointed out there are 88 cases in that cluster – all of which are in isolation.
Ardern also said that there have been 170,500 Covid-19 tests taken since the new outbreak began.
"To put that in perspective," Ardern said, "the World Health Organisation this week said we have one of the highest rankings in the world for our rate of testing per positive case."
This is despite repeated claims by US President Donald Trump that New Zealand is experiencing a massive outbreak.
In her opening comments yesterday, Ardern specifically noted that the US has more than 16,500 cases per one million people.
New Zealand, meanwhile, has 269 per million people, she said.
Asked later in the press conference about Trump's comments, Ardern said New Zealand's approach has been different to other countries.
"But it's an approach I think we can all feel very proud of."
She did, however, warn that New Zealand might never know exactly how this second wave of Covid-19 got into the country.
Officials have been chasing a number of theories and have so far ascertained that the new wave of Covid-19 is from the B111 family.
That specific strain of the virus was rare during the country's first wave, meaning it's "highly unlikely" to be linked.
Tests also show that New Zealand's B111 has not mutated very much from those reported overseas, meaning it's likely the new strain has had a short transmission chain.
It was this type of forensic testing that helped officials determine that the St Lukes case was linked to the Auckland cluster.
Although experts are still investigating the Covid case, Bloomfield said one avenue they were looking into was a bus trip this person took on August 12.
Officials have established that another case, which is part of the wider Auckland cluster, may have been on this bus at the same time as the St Lukes worker.
Meanwhile, eight people from the Auckland cluster are in hospital – one in the ICU at Middlemore Hospital.
There are 143 people linked to the Auckland cluster who have been moved to an isolation facility.
That includes 70 people with positive tests.
Looking ahead, Ardern said there were a number of factors that Cabinet would be looking at before it makes its decision on Monday.
The trends of the virus' transmission will be under the microscope, as well as the level of testing and contact tracing in Auckland.
How effective the isolation period has been will be looked at in detail, as well as how New Zealand's health system would fair if restrictions were eased.
Ministers will also consider the economic impacts of lockdown when they are making their decision.
"So much rests on activities in our biggest city this weekend," Ardern said yesterday.
"Stay the course, short and sharp, hard and early, we've done it before and we can do it again."