Police will do random spot checks on Aucklanders leaving the city for summer roadtrips after travel restrictions ease.
Travel will be allowed into and out of Tāmaki Makaurau from December 15 for the fully vaccinated or those with a negative Covid-19 test.
But Police Commissioner Andrew Coster told Morning Report those travelling should expect to be tested.
"Think about it similar to our approach with breath testing - anywhere, anytime."
Coster said police always had discretion when issuing infringement notices but people knew the rules and the unvaccinated should follow them if they wanted to avoid being fined and "turned back around" to get a test.
"The reality here is we all know what the expectation is - we certainly will do by the time the date rolls around."
Coster said police would do their best to keep traffic flowing despite the checks.
"It's a spot-checking approach so we're not going to be checking every vehicle, but we will be checking many vehicles and so people should assume that they're likely to get stopped," he said.
"There are lots of different places that we can choose to do this that will keep the [traffic] flow going."
Transport Minister Michael Wood told Morning Report any traffic delays over the summer would be "a small price to pay" for the additional protection the spot checks would provide.
"I would advise people just to plan for a little bit more time for your journeys, bearing in mind that a lot of Aucklanders are going to want to get out."
He said Public Health advice had been considered before making the announcement to open Auckland's borders and the Covid-19 Protection Framework (the traffic light system) would add additional layers of protection.
"This is about how we transition and make sure that we have as much safety and protection built in as possible."
Wood said while a "hard border" would no longer be in place around Auckland, additional protections were being worked through in areas with lagging vaccination rates to ensure a robust spot checking system was in place.
"In particular areas like Northland, where we do know that we want a bit of an extra layer of protection ... we expect the police, iwi and community to be working together to provide some extra support there."
It was likely other road policing duties such as breath testing could take place at the same time as the border spot checks, to "maximise the benefit" of the operation, Coster said.
"I'd expect our people to be having their eyes open to the whole situation, which means looking at road safety, looking at Covid safety - they go together."
Extra staff had already been deployed to operate the border in Auckland and Coster expected more would be required to bolster the police presence on roads around border areas over the summer period.
He wasn't able to confirm that all police working on the border would be double vaccinated but said work on a mandate for constabulary staff was continuing to be worked on with government.
"The vast majority of our people are vaccinated and I don't think it's going to be too difficult for us to get over that line."
Wood said Cabinet was working through a potential mandate for police staff and was on track to confirm what the approach for that workforce would be before the end of November.
"Whether it's police or any other group, we do need to take good advice, we need to get it right, we need to make sure that it's legally robust as well."
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