New Zealanders quarantined on cruise ship amid the Covid-19 coronavirus outbreak will be quarantined again when they return home.
Eleven New Zealanders are on the Diamond Princess in Japan which has had hundreds of Covid-19 cases.
Two more are in hospital after contracting the virus.
Passengers were due to leave the ship on Wednesday but would have to undergo supervised quarantine when they arrive in New Zealand.
Director general of health Ashley Bloomfield said Japanese authorities were testing people as they left the boat but quarantine was still needed.
"The issue we are thoughtful about there is if someone is in the early stages of the disease and not symptomatic at all, they may be brewing the infection but not have a positive test," he said.
The passengers were a higher risk than those who had been evacuated from the disease epicentre of Wuhan because about 10 percent of people on the boat had contracted the disease, Dr Bloomfield said.
Australia has just announced it will evacuate the more than 200 Australians, as well as the New Zealanders, who are on board the Diamond Princess.
Prime Minister Scott Morrison said a Qantas charter flight would fly the passengers from Japan to Australia on Wednesday.
"We'll also be providing spaces on our flight to New Zealanders, I've been in contact with Prime Minister [Jacinda] Ardern and they welcome that arrangement as well.
"New Zealand passengers will be transferred from Darwin back to their quarantine arrangements in New Zealand."
New Zealand's Ministry of Foreign Affairs and Trade has confirmed the offer.
New Zealand consular officials are in close contact with New Zealanders on the ship and are working with Australian and Japanese counterparts on the necessary approvals and requirements for those who wish to be evacuated.
Japanese authorities had suggested some passengers might need to stay on board after Wednesday if they had an elevated risk and were not being evacuated by their countries.
Some of the New Zealanders were distressed at that idea but the government was working to help them, Ardern said.
Otago University epidemiologist Michael Baker said the onboard quarantine was not enough to guarantee the people would be disease-free when they arrived home.
"There will be many surfaces on that ship that have viruses on them because there are so many people who were infected. So as a result it's very hard to control transmission in that setting," he said.
Meanwhile, the 157 people quarantined at a centre in Whangaparaoa after being evacuated from Wuhan are also due to leave on Wednesday.
The government is considering whether to keep it ready to go as a quarantine centre.
RNZ / ABC