If you are one of the tens of thousands of New Zealanders travelling overseas, you should prepare to stay put and seek shelter, says Foreign Minister Winston Peters.
The window for flying home is almost completely closed.
Many countries, like Singapore, are now preventing travellers in transit to try contain the spread of Covid-19, Peters said.
But if you are able to get a flight, you should do it immediately as mercy flights can't be guaranteed.
"We are reaching a point where the best option for most New Zealanders offshore is to shelter in place, by preparing to safely stay where they are."
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Peters said that since warning New Zealanders last week that the window for flying home was closing, it "has now almost completely closed".
"It has become very difficult to return to New Zealand from all around the world."
The Government is still considering the feasibility of mercy flights, but Peters said "there are no guarantees these will be possible in the extremely complex and rapidly changing global situation."
Anyone stuck overseas should now prepare to shelter in place and follow the instruction of the local authorities and the advice of the World Health Organisation.
All New Zealanders overseas should register their details on SafeTravel and review the website regularly as it is always being updated.
And Kiwis still coming into New Zealand should expect to see stricter quarantine rules, Prime Minister Jacinda Ardern said this morning.
Speaking on TVNZ's Breakfast programme, she confirmed that another announcement about travellers still arriving into the country should be expected soon.
"I'm not done with our borders yet," she said.