Less than 12 hours since Auckland moved to alert level 2.5 and already crowds of people are swarming to the city's airport taking the opportunity to travel.

At Auckland Airport's domestic terminal, all seemed to be wearing masks but keeping a 2-metre distance appeared impossible as people navigated their way to the bag drop off and check in.

Rotorua mayor Steve Chadwick said she welcomed visitors to Rotorua, one of New Zealand's tourism hotspots, but advised those who were sick to stay away.

"Everybody is a bit jittery so don't come if you're sick, follow the Covid tracing - there has been big pick up locally, and stick to the precautions that we are all following including wearing a mask."

She said hospitality and tourism in Rotorua had been profoundly affected by the second wave of Covid-19 but she was looking forward to it picking up again.

"During [Auckland's] level 3 we certainly noticed the tap turned off here in Rotorua and it was very noticeable, very marked."

The Prime Minister has urged Aucklanders to follow the city's rules - even if they leave the region.

Speaking to media after a visit to a Kainga Ora development in South Auckland, Jacinda Ardern said that level 2 is about taking responsibility.

"Those rules, we're asking you to apply them not only in your region, but to you yourself as well,  particularly around gatherings."