The Prime Minister is warning Kiwis not to get overly optimistic with the drop in new COVID-19 cases recorded on Sunday, saying it's still too early to tell the true extent of the virus' spread here.
There were 63 new confirmed or probable COVID-19 cases announced on Sunday. That was down from 83 new cases on Saturday.
But Jacinda Ardern says the lower number doesn't necessarily mean the virus' spread has been stemmed.
"Don't read into anything too soon - we need a sustained pattern to know whether we're on the right track and we've had a couple of days but it's not something I want people to read into," Ardern told The AM Show on Monday.
Despite there being fewer new cases on Sunday, the day also marked the country's first coronavirus-related death, with director general of health Dr Ashley Bloomfield announcing that a woman in her 70s had passed away due to the virus.
Speaking on Sunday, Ardern said the death was a "reminder of the fight that we have on our hands".
Ardern said a number of stricter measures had been introduced at the airport to minimise the likelihood of more cases of the virus entering the country.
"We're taking off passengers now in small groups so they can be questioned pretty rigorously. They get information before they leave saying if you don't have a self-isolation plan you run the risk of being quarantined once you hit New Zealand," Ardern told The AM Show.
"People are coming off, they're being questioned. If they're symptomatic they're automatically being put into a facility, hotels and the like. If they don't have a self-isolation plan the same thing happens.
"If they do have a self-isolation plan then they are either escorted to the vehicle that will take them on their own to that plan or they are escorted directly and are dropped there. The police are then doing enforcement checks and over the past couple of days we've had something like 1700 enforcement checks, and by and large people are following through on what's expected of them."
Sunday's drop in numbers was likely related to stricter measures introduced at the border in previous weeks, Ardern said.
"There is a lag for anything that we do to then have benefit."
She said it will still be days until we see the impact of the country moving to alert level 4, which has meant all non-essential businesses must close and Kiwis must stay in self-isolation, allowed out of their house only to exercise or to make trips to the supermarket.
The lockdown will last at least four weeks, after which there is a chance that the alert level in some regions may be dropped if the situation has improved.
"If we have enough intelligence to suggest that we don't have community transmission in different regions then you'd expect that we should be able to move to a lower alert system in those regions - it might not be the whole country.," Ardern said.
"The more people stick to the rules, the more likely that will be."
New Zealand currently has 514 cases of COVID-19.
Globally, there have been more than 685,000 confirmed cases with the death toll standing at more than 32,000.