Face coverings will become mandatory in New Zealand under alert levels 2, 3, and 4 for residents using public transport and ride-sharing apps.
Jacinda Ardern announced the new rule along with the extension of Auckland alert level 3 lockdown on Monday which will now last until Sunday 11:59 pm.
From Monday, August 31, people won't be able to access public transport or ride-sharing transport including Ubers, without a face covering or mask.
"This isn't a decision we took lightly, but we know masks protect you and the people around you. They limit the chance of COVID-19 spreading in places that it is often harder to distance yourself to trace people," Ardern said.
"In the meantime, we again urge everyone in Auckland to wear face coverings when in public generally as we have continued to urge over the past week."
Ardern said the decision was made given the recent transmission of COVID-19 on public transport.
"We have seen some cases now where people have become unwell from a bus journey so this is a common-sense approach to public health."
She added she isn't concerned about a mask shortage despite this mandate.
"I read a brief last night of availability, for instance, our supermarket retailers and others. They still do have availability, they still have orders coming into the country," she said.
"But what we continue to encourage is that New Zealanders explore those alternatives that exist too.
"I know it can be prohibitive, the cost of a specific face mask but there is lots of advice available online and through the All of Government group around how you can fashion at home a face covering that should provide you protection as well."
She said the Government isn't mandating a "singular type of mask" - "as if people are putting in the effort to cover their face, that would then satisfy that order".