Coronavirus: Defence Force, police to patrol streets during New Zealand's COVID-19 lockdown

Police officers and Defence Force personnel will patrol New Zealand's streets to ensure compliance with public health measures as the country goes into lockdown over the next 48 hours.

Prime Minister Jacinda Ardern announced on Monday afternoon that the country is now at alert level 3, moving to the highest alert - level 4 - in 48 hours.

Compliance will be enforced by police and Defence Force personnel.

"I can understand that seeing an increase in presence by police and our military may not be what we're used to in New Zealand, but they will be working together," Ardern said during her Monday post-Cabinet press conference.

"I am advised they have all of the enforcement powers they need. We are now utilizing the Public Health Act and I will be issuing an epidemic notice, which gives us a range of additional powers to move into the status we're talking about - level 4 - and of course we are in a national civil defence emergency."

Alert level 3 requires non-essential businesses to close, including bars and cafés, and the cancellation of all indoor events. Schools will close, except to the children of essential workers. People are expected to work from home.

On Wednesday, it will be escalated to alert level 4. Schools close completely, universities and the vast majority of businesses will be closed and people will be required to work and study from home and to physically distance from everyone they are not in isolation with.

When leaving the house, a distance of 2m between people will be required at all times, and people must only spend time with people they are in isolation with. People will only be able to leave the house for essentials like supermarket shops and for exercise.

This morning outgoing Police Commissioner Mike Bush, who is leading the all-of-government response to COVID-19, warned police will detain and arrest anyone failing to comply with the public health requirements.

"The way I put it is, you're better to stay on the comfort of your own couch of your own home than be cooling yourself on a very cool bench in a police cell," he said.

"If people don't do as they're directed, we'll be out there, and we'll be ensuring that people are complying, because they need to be. This is about saving lives."

The measures will be in place for four weeks at this stage.