New Zealand has taken another stride towards elimination of its COVID-19 Delta outbreak, recording 28 new cases.

Evidence of a clear downwards trend is emerging, with 75 cases reported on Wednesday, 49 on Thursday and 28 on Friday.

Director of public health Caroline McElnay said she was encouraged by Friday’s fall, which comes on day 17 of a national lockdown.

The figure is the lowest daily case number for 12 days.

Deputy Prime Minister Grant Robertson agreed with Dr McElnay that “these results are encouraging” but stressed the need to stick to COVID-19 restrictions.

“These results are encouraging but the job is not yet done,” he said.

Of the 28 cases, 27 are in Auckland and one already-isolating individual is in Wellington.

The total number of people infected in the outbreak is 764, with 43 Kiwis requiring hospital-level treatment and nine in intensive care.

The outbreak has continued to drive record-breaking vaccination rates.

About 89,000 Kiwis were vaccinated on Thursday, or 1.8 per cent of the population.

If those rates sustain, NZ is on track to overtake Australia next week for people vaccinated per capita.

As of Friday, 2.42 million people have had at least one dose, or 47 per cent of the population.

Those vaccination rates also pose a significant challenge for Jacinda Ardern’s government.

The high jab levels are unsustainable under the government’s plan, and Ms Ardern has warned of the possibility of tapering off vaccinations so stock can be maintained.

NZ is vaccinating its population wholly through Pfizer, and is totally reliant on the pharmaceutical company for delivery.

A week ago, Ms Ardern promised a fix to the vaccine strategy “within a couple of days”, with reports NZ hoped to borrow vaccine from another country.

That fix has not arrived.

At the same time, this week Australia has announced vaccine swap deals with Singapore and Britain to bring its stock levels up, solving a similar problem.

Mr Robertson denied Australia beat NZ to the same batch of vaccine.

“I would never say that about our Australian friends. I have no doubt that Australia had been working for some time before they were able to make that announcement. I’m sure it doesn’t happen overnight,” he said.

“We’re very aware of the importance of building on the momentum of the fantastic rate of vaccinations.

“We’re still involved in those discussions, in those negotiations and they’re progressing well. We’re feeling very positive about the situation.”

-AAP