New Zealand has reported 20 new cases of COVID-19, underscoring the challenge facing Jacinda Ardern’s government on the road to elimination.

The cases come ahead of a decision on Monday on New Zealand’s alert levels, with Auckland in a fourth week of lockdown and eagerly seeking a passage out.

On Sunday, Ms Ardern announced a second deal to increase New Zealand’s vaccine stocks.

After banking an extra 250,000 doses of Pfizer from Spain, New Zealand has also agreed to buy 500,000 doses from Denmark, which ends any chance of New Zealand running out of vaccine this month.

Ms Ardern said she was encouraged by a fall in daily case numbers earlier this week, with 15 on Wednesday, 13 on Thursday and 11 on Friday.

However, the weekend has seen a jump: 23 cases were reported on Saturday and 20 on Sunday.

“I want to acknowledge how hard it is when numbers jump around as they have been in the last few days,” Ms Ardern said.

“It’s not a sign of failure. It’s not a sign what we’re doing isn’t working. It just means Delta is harder.

‘Mystery cases’

Ms Ardern downplayed reports of “mystery cases” saying advice from health officials was that “we still know where the vast majority of cases are coming from”.

While 1.7 million in the Auckland region are in alert level four, the rest of New Zealand is in alert level two, which gives Kiwis back many of their freedoms.

Ms Ardern refused to foreshadow that decision, saying she would wait for the latest health advice.

“We now have the supply that we need to keep up what has been record-breaking rates of vaccination in New Zealand,” Ms Ardern said.

“There is nothing holding us back.”

-AAP