New Zealand should buckle down, with the border unlikely to be reopened for several months, according to Health Minister David Clark.
Last night it was announced anyone who wasn't a permanent resident or citizen, or a partner or child of, was banned from entering the country.
It was brought in last night and effective for any flights departing for New Zealand past 11.59pm NZT.
The ban comes after last week's requirements for anyone entering the country to self-isolate.
But it quickly became clear it wasn't a practical solution, with groups of tourists refusing to follow the rules.
Foreign Minister Winston Peters says most of the 28 confirmed cases have been New Zealanders returning from overseas.
"At 28 cases, it's clear our best chance of getting on top of a potential outbreak is to shut the country down as much as we can now," he told TVNZ1's Breakfast this morning.
When asked how long people could expect the restrictions to be in place, Dr Clark told Breakfast it could be months.
"We need to prepare for the fact it's not going to be next week, and it's unlikely within the next three months," he says.
"It's looking like longer term... We are going to be in this for the long haul.
"There will be a future time when tourists can visit New Zealand again, but now is not that time."
Anyone who does arrive will still need to undergo a 14-day self-isolation period, regardless of which country they came from.
Mr Peters is continuing to urge all New Zealand travellers overseas to come home, saying around 80,000 Kiwis are travelling on a short-term or holiday at the moment.
As countries continue to bring in their own restrictions, airlines are grounding their planes and reducing flights.
"Make a decision as fast as you possibly can if you want to come home. We can give all the help we can, but you've got to make a decision now," Mr Peters says.
Twenty-eight people have been diagnosed with the coronavirus Covid-19 in New Zealand so far.
The next Ministry of Health update is expected at around 1pm and will be live streamed on 1NEWS.co.nz and the 1 NEWS Facebook page.