Saturday's update is the first daily report since the pandemic began, in which the tally reduced from the previous day, when 85 new cases were announced.

However, that minute drop comes amid an overall spike in cases as testing of Kiwis returning home from international travel has increased.

Health officials carried out more than 11,000 tests in the past seven days, a period when cases of the virus surged by almost 900 per cent.

Last Saturday, New Zealand had just 53 cases of the virus. The country is yet to record a COVID-19 related death.

Among the 451 cases, 50 have recovered and just 12 require hospital treatment.

Two are "critically unwell" in intensive care units, with one requiring support from a ventilator to stay alive.

One is a man in his 70s with underlying health conditions at Nelson Hospital.

New Zealand is on day three of a four-week government-ordered lockdown which aims to reduce transmission by cutting out socialisation between Kiwis.

As of Saturday, Kiwis are barred from domestic travel between cities, or from travelling on the ferries that link North and South Island.

Air New Zealand has also emailed staff to announce a small number of the airline's employees have tested positive to the virus.

Australian Associated Press