Coronavirus: People are 'being held accountable' for Government's COVID-19 quarantine debacle, Grant Robertson says

People are being held accountable for a Government blunder that saw two active COVID-19 cases allowed to leave a quarantine facility early, Grant Robertson has confirmed.

Two sisters who returned to New Zealand from the UK on June 7 were granted a compassionate exemption from managed isolation at Novotel Ellerslie last Saturday, following the death of their mother.

The women, who later tested positive for coronavirus, were allowed to leave despite one exhibiting symptoms and neither being tested for the disease prior to their journey.

It has since been revealed that Health Minister Dr David Clark doesn't know how many other people may have left quarantine without being tested.

Speaking to Magic Talk on Thursday morning, the Finance Minister echoed Prime Minister Jacinda Ardern's comments a day prior, describing what had occurred as a "breakdown in the system".

And he was adamant those responsible were being taken to task for their role in the botch-up.

"They are [being held accountable]. You would've heard the Director-General of Health [Dr Ashley Bloomfield]... has accepted things were not implemented the way they were meant to be," he told host Peter Williams. 

"But you'll also understand, from our perspective, our focus is on fixing this breakdown in the system. It's not acceptable what's happened, and that's why we've brought in some support from the deputy chief of the Defence Force.

"At the same time, we've also got to acknowledge we've had many thousands of people come in through the quarantine process and it's worked relatively well - but that doesn't excuse this situation, and that's why we're fixing it."

Robertson says there were changes made to formalise testing on day 3 and day 12 at managed isolation and quarantine facilities - but that wasn't implemented in this case, despite being the protocol.

"There was a breakdown here, we're gonna make sure it's not gonna happen again," he said.

But the raft of changes announced by Ardern on Wednesday might be too late to prevent a fresh COVID-19 outbreak in New Zealand, with test results from the 320 people potentially exposed to the two women yet to be reported by the Ministry of Health.

Robertson says it'd be "hugely disappointing" if the mistake caused a fresh outbreak in New Zealand.

"When we catch cases at the border, that's the system working well - but if there were a resulting transmission as a result of this, it'd be enormously disappointing for all New Zealanders," Robertson said.

"But let's see what happens over the next few days in terms of testing of the close contacts."