New Zealand will assist in evacuating people from coronavirus stricken cruise ship

New Zealand will assist Australia in evacuating citizens trapped on a cruise ship contaminated with coronavirus.

Prime Minister Jacinda Ardern confirmed on Tuesday Kiwis trapped on the Diamond Princess in Japan will be offered the opportunity to be evacuated alongside Australian citizens.

"We have communicated to New Zealanders that the offer is available," she said on Tuesday. 

Anyone who chooses to be evacuated will need to be quarantined for a further 14 days despite having already spent a fortnight in lockdown on the cruise. 

Anyone who does not choose to be evacuated will have to be quarantined in Japan before they can return to New Zealand.  

"I understand how frustrating that will be for them," said Ardern.

"But unfortunately there has been such a rate of transmission that we need to put public health and their health first and undertake further quarantine."

There are currently 11 New Zealand citizens on the cruise. Two have been hospitalised with coronavirus.

Ardern said she and Australian Prime Minister Scott Morrison are "working through" the details of the flight, including what provider will be used.

"We are investigating a range of options and it looks most likely we will engage a specific commercial operation which is just for [the evacuees]," she said.

Ardern said Australia will undertake the primary evacuation if it's 200 citizens back to Darwin. She did not specify how New Zealand citizens would be brought back home. 

"It is Australia that's primarily bringing [its evacuees] back to Darwin so we need to talk about that," she told media. 

The United States evacuated its citizens from the ship on Saturday. The Diamond Princess has been docked in Japan since early February after a man who disembarked in Hong Kong was diagnosed with the virus.

Roughly 3700 passengers and crew have been isolated as the virus tears through the ship. At least 355 people onboard have contracted the disease, according to Australian Health Minister Greg Hunt. 

'War without smoke'

The epidemic has killed 1770 people in mainland China and infected more than 71,000 globally.

It has been described by New Zealand's Chinese ambassador as "a war without smoke but certainly not without casualties".

Wu Xi said on Tuesday the prevention and control of the epidemic is China's biggest focus. 

She likened it to "working a miracle".

The coronavirus, now known as Covid-19, originated in the city of Wuhan in China's Hubei province late last year. 

It's thought the disease spread from animals to humans in a live food market. 

Since the virus broke out, it has spread to more than 25 countries, causing fever, coughing, respiratory distress and pneumonia. In severe cases, it can lead to organ failure and death.