The Council of Licensed Firearms Owners has apologised after sending its members an email suggesting "how to vote" which included an authorisation statement from the ACT Party.
In the email, members of the firearms advocacy group were advised against voting for Labour, the Green Party, New Zealand First or New Conservatives.
Instead, it advised members to vote for National or the ACT Party for policies surrounding firearms use.
The email signed off with an authorisation statement from the ACT Party. COLFO chairman Michael Dowling says that was a mistake.
"No political parties have authorised our ‘How to Vote’ message," he said in a Facebook post .
"I alone authorised it as chairman of a non-partisan organisation singularly focused on licensed firearm owners."
Nicole McKee, who is third on the ACT Party's list, was the former chairwoman for the council and a frequent public speaker on firearms advocacy.
She resigned from the council after announcing she would be standing in the election.
The authorisation signature "was a residual from a previous message to members" from McKee when she announced she would no longer be a COLFO spokesperson, Dowling says.
"I unreservedly apologise to the ACT Party for this oversight. I regret any confusion this may have caused."
When contacted by 1 NEWS, a spokesperson for the ACT Party said the authorisation statement was used in error.
“When Nicole McKee stepped down from COLFO to contest the election, the organisation’s members were advised via email," the spokesperson says.
"As a precaution, ACT’s authorisation statement was added to the email template. The same template was subsequently used in error."
Under the election advertising rules, any election advertisement needs to include a promoter statement including the name and address of the person promoting the ad.
An "election advertisement" is classified as "an advertisement in any medium that may reasonably be regarded as encouraging or persuading voters to vote or not vote for a candidate, party, type of candidate or party the advertisement describes by referencing views they do or don’t hold", according to the Electoral Commission.