Police will patrol major Auckland transport hubs to ensure people are complying with new rules that make it mandatory for face masks to be worn on public transport.

The new regulations come into effect at 11:59pm on Wednesday and will apply to everyone over the age of 12 travelling on public transport in and out of Auckland. The drivers of small passenger service vehicles in Auckland, such as taxis and app-based ride services, will have to wear them too, but not their passengers.

Masks will also be required on all domestic flights across New Zealand.

A police spokesperson said officers will be stationed across Auckland to help with compliance.

"Police will provide reassurance patrols across major Tāmaki Makaurau transport hubs and will take a similar approach to that used previously. This may include the handing out of face coverings where appropriate," they said.

It will take an "education and encouragement" approach to the wearing of face masks.

"Throughout the COVID-19 response Police has found that our communities have responded well to increased restrictions, that people know what is expected of them and that they have done their part to keep all New Zealanders safe."

Prime Minister Jacinda Ardern said on Tuesday the new changes were the "latest tweaks to our system".

"One of the reasons we're moving now is because we're seeing more and more our ability to actually manage these known outbreaks connected to quarantine facilities at a level 1 environment," she said. 

"Previously, of course, we do already have compulsory mask use at level 2. Our view is, while we get better at managing these situations at level 1, we need to bring those precautionary approaches with us."

She described the new rules as another line of defence.

"So why wouldn't we use that? Particularly in environments like buses where it's harder to contact trace people. We've always encouraged ongoing mask use on planes and public transport... but we want to see that usage enhanced, so that's why we're moving to mandating."