Prime minister Jacinda Ardern is self-isolating after being deemed a close contact of a positive Covid case.

She was on the same flight - NZ8273 from Kerikeri to Auckland - as an infected person last Saturday.

Governor-General Dame Cindy Kiro was also on the flight and is isolating.

Both were in Northland undertaking advance filming at the Waitangi Treaty Grounds for the Waitangi Day broadcast.

The prime minister is asymptomatic and is feeling well, her office said.

In line with Ministry of Health advice she will be tested immediately tomorrow and will isolate until Tuesday, a press statement said.

She is fully vaccinated and received a booster shot on 17 January.

The flight was added to the Ministry of Health website as a location of interest this evening.

All other passengers on board are also deemed close contacts and are required to self-isolate.

Genomic sequencing results are expected tomorrow and will indicate if the infected passenger was infected with Omicron or another Covid variant.

The prime minister went into self-isolation as 97 new community cases were reported today, with 11 new Omicron cases identified in the community.

The new community cases were in Northland (1), Auckland (61), Waikato (14), Tairawhiti (3), Bay of Plenty (8), Rotorua (7) and Hawke's Bay (3).

There are now seven people in hospital with Covid-19 - none are in intensive care.