The Government is advising New Zealanders not to travel overseas due to coronavirus.

Foreign Minister Winston Peters issued the warning on Thursday and said the Government was also looking at 'mercy flights' to bring home Kiwis stranded overseas.

This is the first time the Government has advised New Zealanders against travelling anywhere overseas, which reflected the seriousness of the situation the country was facing with Covid-19, Peters said.

No time frame had been set but it would last until the Government could be assured travel was safe for the domestic population, he said.

"We are raising our travel advice to the highest level: do not travel," Peters said.

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"New Zealanders who travel overseas risk contracting Covid-19. At the same time, health care systems in many countries are under strain and do not have the capacity to support foreigners."

More than 80,000 Kiwis could be left stranded overseas and Peters again urged all New Zealanders currently travelling to consider returning home immediately.

However, some are struggling to follow that advice as commercial flights begin to dry up.

Peters said the Government was putting plans in place to bring back Kiwis and this included mercy flights.

"We have to anticipate that if we have a lot of people off shore who can't get home, we may be able to send them to one place where we could get a plane to them and bring them home and go through all the security measures."

He had a message for those Kiwis who did not want to bring the 80,000 home: "Put yourself in their shoes. They are New Zealanders, fellow countrymen and women and members of your family. We have got to think bigger than that."

The number of SafeTravel registrations had jumped from 17,000 to 20,000 overnight, he said.

"Borders are closing. You may not be able to return to New Zealand when you had planned to. You should therefore organise to come home now," he said.

KATHRYN GEORGE/STUFF Coronavirus is transmitted by droplets, often from the lung and sent by coughing or sneezing.

"If you choose to remain overseas despite our advice, the ability of the New Zealand Government to provide consular assistance may be limited due to internal travel restrictions and the suspension of services.

"Those New Zealanders who are long-term residents outside New Zealand will need to consider their personal circumstances and do what is best for them and their family," Peters said.

New Zealanders who decide to remain overseas would need to ensure they were well prepared, he said.

"New Zealanders in this situation should keep themselves safe by following the advice of the World Health Organisation (WHO) and local health authorities. New Zealanders overseas are also encouraged to register on SafeTravel so they can receive important updates on COVID-19."

"In times of crisis, we will see the best in people, and the worst. To those who say we should not welcome our fellow citizens back to our shores I ask that you put yourselves in their shoes.

"All New Zealanders need to show their compassion for one another. Now, more than ever."

Peters said the travel ban would not apply to him or Trade Minister David Parker because they may need to travel in emergency situations and in the interest of long-term trade.

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