A Labour Party ad featuring Prime Minister Jacinda Ardern, with a brief appearance by director general of health Ashley Bloomfield, then not, has been taken down.
The Facebook ad featured a visit by Ardern to the Institute of Environmental Science and Research (ESR) and the national contact tracing centre.
The original ad also featured a three-second appearance by Bloomfield.
However, the ad was later taken down for a re-edit, which did not feature Bloomfield.
Act leader David Seymour described the ad as scandalous and said no public servants should be used to help political parties campaign.
But a spokeswoman for Ardern said the advert did not break any rules.
"To even think it might be okay to go and use a government department to shoot a political ad is just extraordinary," Seymour said.
"One of the hallmarks of a democracy is you don't get to use the power of Government for your own re-election."
When first contacted by the Herald on Saturday afternoon, a spokeswoman for Ardern denied it was a Labour campaign ad.
"The video is an update on the Government's Covid response and specifically the work ESR and the national contract tracing team has been doing," she said.
"The Prime Minister's updates are shared on the Labour Party channels as it permitted within the rules," she said.
A spokesperson for the Taxpayers' Union told the Herald on Sunday morning their lawyers "are currently in the process of preparing a complaint to the State Services Commissioner".
"Taxpayer-funded civil servants should not be made complicit in the governing party's political propaganda."
The spokesperson said it was a "clear breach" and wondered if it was done deliberately.
"They would have known that even after deleting it the controversy will mean many more people will see it."
Ardern made the visits on Thursday.
News media were restricted in the number of cameras and reporters at ESR in Porirua where genome sequencing work is being done on Covid-19 cases.
Reporters were not told about Ardern's visit to the national contact tracing centre.
Ardern and Bloomfield have shared the stage many times during the Covid-19 crisis, including the 1pm briefings.