No patients are in hospital with Covid-19 for the first time since New Zealand went into lockdown.

The good news comes as director general of health Ashley Bloomfield reveals there are no new Covid-19 cases today. It is the fifth day in a row since New Zealand has recorded a case. There are only 21 active coronavirus cases, he says.

Bloomfield said back in alert level 4 a lot of people got out to exercise and he encouraged them to continue those habits.

If you can maintain that level of physical activity, that would help you to stay healthy over winter, he said.

The Ministry was continuing to work with the Ministry of Transport to promote the benefits of walking and cycling.

The move to alert level 1

The Ministry advice given to Cabinet on Monday was for another four weeks at alert level 2 and at the moment that advice stands, Bloomfield said.

Officials wanted to be certain that relaxing activities didn't come with more infections.

The Ministry was "working hard" on what alert level 1 would look like and what arrangements would need to be in place for the transtasman bubble.

The Ministry has asked for more advice on when masks should worn from various technical advisory groups.

That advice is still being finalised and would be made available in the last few days.

International students to return?

There's a piece of work underway to allow international students back into the country, but everyone coming in would need to comply with quarantine or managed self-isolation.

There have been just three new cases of Covid-19 in the past fortnight.

On Monday, the Ministry of Health said New Zealand would eliminate the virus if there are no new cases for at least 28 days and the country continues to have strong border measures.

The last confirmed case was on May 22, and was a household contact linked to the St Margaret's cluster in Auckland.