The Prime Minister is warning against expecting perfection at the border as NZ Defence Force troops are brought in to tighten the regime which has seen two strains of Covid-19 infections escape.

Jacinda Ardern has also brought in two top advisors to spearhead the testing strategy after failings saw frontline border workers go untested.

But she has been sideswiped by her coalition partner this morning, with NZ First leader Winston Peters saying he'd been pushing for the military to lead border protection efforts before the first lockdown - for a fifth of the price of hotels.

It comes as epidemiologist Sir David Skegg is calling on the Ministry of Health to release data on the number of people infected by this outbreak who had previously tried to get a test but were denied one.

"With spread of this virus, every day counts. Unfortunately the continual changes in criteria for testing in the community led to an unsatisfactory testing performance."

Skegg said the testing staff at the border - including at airports and sea ports, along with those managing isolation and quarantine facilities - had been "even poorer than some of us feared".

This was because the Government had relied on people voluntarily being tested and "partly due to a clear failure" in executing the testing strategy.

On June 23, Cabinet agreed on a testing strategy but it was slow to be implemented with many border-facing workers - including about two-thirds of MIQ workers - not being tested at all before the latest outbreak.

Deputy Prime Minister Winston Peters told Newstalk ZB's Mike Hosking today that the Defence Force should have been leading border protection efforts from the start.

He said the Government could not have people being assured something was happening and when inquiries were made, this was found not to be the case.

The military worked along far more disciplined and organised principles. "We can't have people doing what they like."

"We asked for the military to be used before we went into lockdown in the first place. You have your biggest city in the country, we're bringing people into there, threatening the huge population. We could have isolated properly, in my view, and ensured people were safe and we were not endangering the population of the country."

Peters said military facilities at Whangaparāoa, Ohakea, Burnham, Waiouru and West Melton could all be used. "We have got the facilities, we have got the land and we have the soldiers. The cost [when] put against the hotels could be $1 to $5."

Meanwhile, Peters felt the High Court had got it wrong with its decision that ruled the first nine days of New Zealand's original lockdown were unlawful.

"I'll give you my perspective, only mine," he told Hosking. "We had a disquiet that the laws of this country were not sufficient for an occasion like this. I wasn't surprised. It was only nine days. I still disagree in some context with the court's decision - in the end the number one responsibility of any member of Parliament, let alone a minister or the prime minister, is the safety and security of the population of New Zealand. In that context, I'm still prepared to say I think the court has got it wrong."