Masks will be compulsory for travellers on all planes flying domestically around New Zealand, and on all public transport in Auckland.
Prime Minister Jacinda Ardern confirmed the move today, after Covid-19 Response Minister Chris Hipkins signalled his desire last week for mandatory mask use.
Ardern said additional precautions were needed under Alert Level 1.
From Thursday morning, masks will need to be worn on all public transport in and out of Auckland, and on all aircraft.
School buses and charter services are exempt. Children under 12 will not have to wear a mask. Police can enforce the new rules.
"No system is fool-proof and transmission can occur," Ardern said when explaining why the new measures have been put in place.
Hipkins said they were looking at whether mandatory mask use on public transport should be extended to other areas, and the rules around QR codes.
"The Government is seeking further advice from officials about extending face covering requirements for other centres and introducing mandatory scanning of QR codes in some high risk situations where contact tracing is challenging," Hipkins said.
Last week, a positive community Covid-19 case was confirmed in Auckland. Director of Public Health Caroline McElnay said genomic sequencing shows that infection has been directly linked to the recent case of a defence worker at the Jet Park Hotel quarantine facility.
There has been no shift in alert levels since the November quarantine cluster formed, with the country remaining at Alert Level 1.
At Alert Level 2, mask wearing was compulsory on public transport and planes.
Public health expert Michael Baker said yesterday that having clear rules around the use of masks will help dampen down the threat of community transmission and avoid another lockdown.