The Government is "finalising arrangements" for additional Pfizer vaccines to supplement stocks this month, to ensure the immunisation rollout continues at pace.
Prime Minister Jacinda Ardern said a deal was being finalised for additional Pfizer vaccine supply in September, before the large vaccine shipments arrive in October.
It was a multi-country deal.
As the deal was still being finalised, Ardern would not say which specific countries were involved or give additional details prior to the contract being signed.
"When the Delta outbreak began, we had a choice," Ardern said, to follow the plan which accounted for the supply in New Zealand, or step up the rollout.
"Our view was that when Delta arrived, we needed to surge up those vaccines even if we didn't have the supply available, and work to do everything we could to meet that demand.
"There was never a chance of running out but we didn't want to dampen down the demand we saw."
She said demand had increased 180 per cent, compared to prior to the Delta outbreak where the Government had planned for 350,000 doses to be administered a week.
"But what we saw when we provided that extra capacity was demand go well over half a million a week."
"We needed to obtain additional supplies, this will supplement out stocks until our large shipments arrive in October."
The Government contacted Pfizer and other countries to negotiate additional supplies in the last few weeks.
"To say they were complex would be an understatement".
"We will share further information as soon as we are able."
The Government had been hinting last week that there would be an announcement surrounding vaccines in the coming weeks.
National's Covid-19 spokesperson Chris Bishop said the announcement "is good news but begs the serious question, why didn’t the government do this earlier in the year?"
"The Government shouldn't have needed a Covid Delta outbreak in the community to spur it into action.
"It should have been securing as many Pfizer doses as quickly as possible from the start of this year, to protect New Zealand against the Delta variant and to speed up our process of reconnecting to the world."
National leader Judith Collins said recently the Government "wasn't really straight up with Kiwis" about the state of vaccine supply.
"It now turns out we've got some vaccines being contracted from other countries to supply them," Collins said.
"The main thing is to get vaccines into people's arms as fast as possible and make sure we order the boosters."
On Monday, more than 66,000 doses were administered, pulling the total to date up to 3,958,607. More than 1.3 million people have been fully vaccinated.
It follows Australia's deals with the UK, Singapore and Poland to address the Pfizer vaccine shortage while it grapples with a Covid-19 outbreak.
ACT leader David Seymour raised the issue of vaccine supply matching New Zealand's need, after calculations made using data on the Ministry of Health website indicated supply could run out in the next few weeks if more vaccines did not arrive.