Being vaccinated against Covid-19 could be considered as a condition of employment for new district health board employees.
Such a requirement will be a condition for new employees working on vaccination sites or in managed isolation facilities.
However, the Lakes District Health Board has confirmed it could also be consideredas a condition of employment for new employees in "patient-facing roles".
Ardern said on Thursday that from Monday, unvaccinated border workers would start being moved to other work and on Sunday's airing of TVNZ's Q+A, she said they would have up to the end of the month to be vaccinated or moved.
"We are moving into the phase where the window is closing ... we have already set down that the period from Monday through to the end of this month - if in that period they are not vaccinated, they are redeployed," she said.
"That is really the last call."
Copeland Ashcroft partner Myriam Mitchell said it was easier for an employer to require new employees to be vaccinated than for existing employees.
"Generally speaking, employers are free to set the terms and conditions of employment at the start, so essentially if an organisation had done a risk assessment from the health and safety perspective and they consider the vaccination is an important part of controlling risk, then it is up to that organisation to say this role needs to be filled by someone who is vaccinated."
Employers could also ask for proof of vaccination, Mitchell said.
However, an employer cannot decline a candidate who is not vaccinated due to medical reasons as employers could not discriminate under the grounds of medical disability, she said.
"But then again, that discrimination can be lawful, where you would otherwise be putting that person into a position where their safety is at risk or you're putting other people's safety or health or safety at risk."
Requiring existing employees to be vaccinated was a hard task if it was not already written in the terms and conditions of employment but employers could support people to be vaccinated to ensure they were responsible employers.
In regards to redeploying workers, Mitchell said an assessment on the necessary need of vaccination for the role would need to be undertaken before a period of consultation, rather than automatic redeployment.
"The employer will need to meet their good faith obligations in terms of consultation and going through a process with the employee and also a health and safety risk assessment to show it's a requirement for the role now.
"It might be a little bit more akin to going through a restructuring process."
A Lakes DHB spokeswoman said the vaccination would be a condition of employment for new employees who were working on vaccinations sites or in the border setting.
The majority of workers in Rotorua managed isolation facilities, and those at the Port of Tauranga had received their first dose of the vaccine and were awaiting their second dose.
Bay of Plenty DHB Covid-19 incident controller Trevor Richardson said as of midday last Wednesday there has been no recorded "declines" on the immunisation register.
About 450 to 500 port workers were eligible for the vaccination and the programme was expected to finish on April 16.
"As of noon April 7, 467 border workers have received at least one dose of Covid-19 vaccine, along with 336 border worker's whānau members. Six-hundred-and-sixty-eight frontline health workers have now also received the Covid-19 vaccine."
Vaccination was voluntary for all Port of Tauranga employees, a port spokeswoman said.
"The vaccine is just another tool to keep our people safe from Covid-19. They still need to take all of the other precautions that have worked for the past year - distancing, wearing PPE when required, hand hygiene and getting tested regularly."
Bay of Plenty District Health Board executive director of people and culture Joseph Akari provided the same response as that released by the Government.
"The Government has confirmed the vaccination will not be mandatory. As health workers, we are all keenly aware that individuals have the right to refuse medical treatment under the Bill of Rights Act."
When pushed on whether the vaccine was considered as part of general health and safety protocol, such as PPE, Akari said, "PPE is part of the controls that we have in place at the DHB, as is good hand hygiene."
"The Covid-19 vaccine is a new layer of control we have at our disposal."
A Ministry of Health spokesman said if a patient contracted Covid-19 from a DHB staffer, a claim for compensation against the DHB would be impossible.
"In this instance, any claim for compensation against a district health board is likely to be precluded by section 317 of the Accident Compensation Act 2001, where the infection of the patient constitutes a treatment injury under the Act.
"The exception would be in the event of gross negligence on the part of a DHB gave rise to a potential claim for exemplary damages as set out at section 319 of the Act."