Covid-19 Response Minister Chris Hipkins says the vaccination rate for port workers is "far too low".
He was commenting on the 3800 non-MIQ border workers who are yet to have a single dose of the Pfizer vaccine.
It's unclear how many of them are subject to a public health order, which requires all MIQ workers and all Government employees at the border to be fully vaccinated in order to work on the front lines.
Privately employed border workers outside MIQ, including cleaning, retail and hospitality workers at the port or airports, are not subject to the order.
Hipkins said most of the border workers who have not been vaccinated were port workers.
Port workers were lower risk than airport workers, he said, but he noted the port engineer who caught Covid-19 at the workplace last year.
"The length of time it takes for a ship to get here obviously reduces the risk, but it's not no risk."
There were vaccination sites at ports, he said.
"But ultimately, making the sites available and getting people to come forward for vaccinations are different things."
Air NZ said at the weekend that 21 per cent of its frontline workers are yet to have a single vaccine dose, but Hipkins said many of them were involved in transtasman flights, which were lower risk.
"There's a lot of work going on just to follow through those last groups, but the ports certainly seem far too low. That's an area where there's definite need for more attention.
"We want to see higher rates."
Border workers are meant to be at the top of the queue for vaccination, and almost all of the 4500-odd MIQ workers have been fully vaccinated.
The Government also wants an estimated 50,000 household contacts of border workers to be fully vaccinated to create a vaccinated safety barrier at the border.
But only half of them have had at least one vaccine jab.
"I'd like them to come forward and be vaccinated, [but] it isn't compulsory for them," Hipkins said.
He said others in the group might have been vaccinated but they haven't been recorded as a household contact.
"People might come forward for more than one reason ... We don't track and trace everybody that works at the border in terms of who they come into contact with."
There are an estimated 13,000 border workers over a fortnightly period. That includes about 4500 workers in MIQ facilities.
Of the remaining 8500 non-MIQ border workers, about 4500 of them were fully vaccinated as at 9pm on June 1, while 200 have had one Pfizer jab.
That leaves about 3800 border workers at airports and sea ports, or transporting to and from there, who are yet to have a single vaccine dose.
Ministry of Business, Innovation and Employment figures show about half of the 50,000-odd household contacts of border workers were also yet to have a single vaccine dose.
Figures released to the Weekend Herald also show about 1100 workers at the border who are not getting tested within the required timeframe.
Director-general of health Dr Ashley Bloomfield also confirmed to the Weekend Herald a non-compliance rate of 4 per cent for MIQ workers getting tested regularly. This translates to about 180 MIQ workers.
The rate for non-MIQ border workers was 14 per cent - or about 930 workers.
The Health Ministry said about a third of them were less than four days overdue when they were tested, and because it took a few days to update the border worker testing register, some of them might well have been tested within the required timeframe.
Bloomfield said non-compliant workers weren't necessarily missing their tests.
"There will always be people, maybe those who have gone on leave, or they're on days off - [so] they're a day late."