New Zealand has reported its biggest rise in Covid-19 infections in six weeks, with all cases detected in Auckland, raising prospects of a further extension of lockdown restrictions in the country's largest city beyond next week.

Deputy Prime Minister Grant Robertson said the surge in case numbers in Auckland was not unexpected “but they are rising more quickly,” and blamed illegal home gatherings for the spike.

“Now is not the time for complacency,” Robertson said during a media conference in Wellington, urging residents in Auckland to strictly follow the level-three rules, under which most people are required to stay at home unless they have urgent reasons to go out.

A total of 71 new local cases were reported in the country, all detected in Auckland, up from 55 a day earlier, according to a Reuters report.