Coronavirus: Jacinda Ardern explains why alert level 4 lockdown has been extended

New Zealand has sacrificed too much to end alert level 4 now, the Prime Minister has explained, after revealing the Government would be extending its nationwide coronavirus lockdown.

Jacinda Ardern announced on Monday that COVID-19 alert level 4 will now be in place until 11:59pm on Anzac Day - five days later than originally planned.

From April 27, New Zealand will deescalate its coronavirus response to alert level 3 for two weeks before making another decision on whether to change levels again.

The Prime Minister says the reason for the decision is to ensure all the ground gained during the COVID-19 outbreak by staying home doesn't count for nothing.

"The message to New Zealanders is you have sacrificed too much to lose those gains now," she told media in a press conference from the Beehive theatrette on Monday afternoon.

"Let's lock them in and do everything we can not to go backwards, and keep moving forwards successfully.

"Every point along the way, we are having to make sure we are looking at the health impacts and economic impacts. But thankfully for New Zealanders, both point to the same path: fight the virus, save lives and save livelihoods."

Ardern says the decision was made as late as possible - over the weekend - to ensure the Government made its call based on up-to-date health and economic data.

"This decision has really fallen into place based on all of the evidence, the modelling, the research and the advice, and we have agreed with the recommendation from the Director-General of Health," she explained.

"My view is I've always been willing to wait for the latest information and data we have, to get the best modelling and advice we can. So we only started considering that over the weekend when we had that information in front of us, so we could do it in real-time."

The Prime Minister acknowledges the extension of alert level 4 may be a difficult pill to swallow for some Kiwis - particularly non-essential business owners and families dealing with the deaths of loved ones - but says she trusts them to understand the rationale behind the decision.

"Just as I came down I was shown an email from someone who has lost a loved one, who said that they were one of the families who have been affected by the funeral arrangements - but to reinforce them, not to change them," she said.

"That to me is the extraordinary courage of New Zealanders, who in spite of feeling so acutely the sacrifices that they're making, believe in the mission we have together." 

Next Monday, New Zealand will enter alert level 3 for at least two weeks. Among other changes, this will see some non-essential businesses and recreational activities allowed to resume.