Coronavirus: Jacinda Ardern says Kiwis will have to go into isolation in Japan if they reject evacuation via Darwin

Prime Minister Jacinda Ardern. Photo / Mark Mitchell

New Zealand passengers who have been quarantined on the Diamond Princess cruise ship in Yokohama will have to undergo further isolation in Japan if they don't return to New Zealand via the planned Australian evacuation, says Prime Minister Jacinda Ardern.

Ardern told reporters at Parliament that she had spoken again to Australian Prime Minister Scott Morrison last night about the evacuation of 200 Australians from the ship and the offer to include the 11 New Zealanders.

The evacuation tomorrow will involve a flight from Japan to Darwin with the Australians and then a further flight chartered by the New Zealand Government from Darwin to Auckland for the New Zealand passengers.

The Australians will be quarantined for a further 14 days in Darwin and the New Zealanders on the ship had been told that would need to be quarantined in New Zealand because of the infection rate on the ship, Ardern said.

"We've also told them that if they do not choose to travel on this flight, they will need to undertake a quarantine in Japan before they come back to New Zealand."

She understood the frustration they would be feeling after having already been in isolation for 14 days.

"But unfortunately there has been such a rate of transmission, despite some incredible efforts from all those involved, that we do need to put public health and their health first and undertake a further quarantine."

She said there were some people on the ship who were very distressed and eager to get back to New Zealand and the current quarantine facilities at Whangaparaoa were giving good care to New Zealanders who had returned from Wuhan in China.

Asked if the Government could compel New Zealanders in Japan to go into isolation, Ardern said : "Actually we can say at the border that they will not be able to board so yes, we can take those measures but actually I feel confident we are giving options here. We are giving people the ability to come home and that's important.

"But if they choose not to, we need to keep in mind that if they choose to fly commercially it then exposes a range of other people to risk."

The best option was to come back. If they chose to stay they would need to wait another 14 days.

The Diamond Princess has been in lockdown in Yokohama for about a fortnight with about 3700 passengers but the virus has spread.

About 16 Australians and two New Zealanders have the virus and have been hospitalised for treatment.

The United States has evacuated 300 of its citizens who were on the boat, including 14 whose positive tests for coronavirus came through after they had disembarked.