The Government will today decide if Auckland will join the rest of the country at alert level 1, after eleven straight days of no new Covid-19 cases in the community.

Prime Minister Jacinda Ardern will today announce if the City of Sails will move down from alert level 2 from midnight on Wednesday.

Positive community cases of the virus were last reported in the city on September 23.

Yesterday, Ardern said the country's Covid response had been tracking as expected, but she would not speculate about today's decision.

"Any decision that is made won't come into force until Wednesday; that's because we need to give notice about the rule changes," she said.

Five new cases of Covid-19 were reported on Sunday, all caught at the border.

Of the five people who tested positive, two arrived from Switzerland via the United Arab Emirates and Malaysia on September 29.

One was from Russia via the United Arab Emirates on September 21; another was from Ukraine on September 29; and another was from Australia on September 30.

Two of the returnees were in managed isolation in Auckland.

Yesterday's results were from routine testing around day three for four people and testing around day 12 for the fifth person, the ministry said.

There is now no one in hospital with Covid-19 in New Zealand.

Meanwhile, new requirements for air crew came into effect last night, after changes were made under the Covid-19 Public Health Response Act 2020.

All New Zealand-based air crew must now use PPE on all flights and isolate with other crew members while on overseas layovers, and when in New Zealand.

New Zealand-based crew returning here from high-risk locations overseas now must self-isolate for at least 48 hours after they return, and until they are assessed as being low risk of having Covid-19, including receiving a negative test.

Overseas-based air crew must wear appropriate PPE while in New Zealand airports and whenever travelling between the airport and their hotel.

If they are laying over in New Zealand, overseas-based crews will do so in a Government managed isolation facility for as long as they are in the country, to ensure they avoid contact with New Zealanders.

The ministry said it was aware these measures were already widely used, and this change would make sure they were applied consistently.