There are no places within New Zealand's managed isolation regime for returning Kiwis until March, the government says.

The New Zealand government is widening its criteria for emergency entry into the country beyond its locked-down borders, but there's still no sight of the trans-Tasman bubble.

Entry to New Zealand is unavailable to all but Kiwi citizens and regular residents, including Australians who normally live in Aotearoa.

Even then, anyone without an existing booking faces a wait until March for entry into NZ.

Like Australia, the NZ government has mandated a fortnight's quarantine for all international arrivals, operating a 6261-bed managed isolation and quarantine (MIQ) regime with 32 hotels across the country.

With high demand over summer, a check of the system on Friday showed no available rooms to book until February 15, meaning no release into the community until March 1.

The only prospect for entry before then - without abolishing quarantine - is emergency entry.

On Friday, MIQ boss Megan Main said NZ would adopt a two-tier system for emergency entries.

Category one emergencies involve serious health risks for the applicant or their dependant, or care needs for a child.

The new category two reasons include care-giving, essential healthcare or infrastructure maintenance, Kiwis legally unable to remain abroad, national security reasons, or to visit a close dying relative.

All emergency entries still need to complete the 14-day quarantine.

Ms Main said the decisions were "not easy ones to make".

"We need, however, to balance each individual application with our critical work to ensure the safety of all New Zealanders," she said.

Anyone looking to enter New Zealand must do so by booking a place through the MIQ website.

Earlier this week, Prime Minister Jacinda Ardern poured cold water on the creation of a much-anticipated trans-Tasman bubble this year.

The NZ and Australian governments have different tolerances for community cases, with Ms Ardern seeing her elimination strategy as incompatible with Australia's hotspot suppression approach.

NZ officials did conduct a visit of the Cook Islands last month with a view to open the country's first quarantine-free travel bubble with the Pacific nation early next year.