PM Jacinda Ardern stops short of telling NZ First's Shane Jones off over Facebook gun photos

Prime Minister Jacinda Ardern has stopped short of criticising New Zealand First Minister Shane Jones for shooting a gun, banned in New Zealand, at a firing range while on holiday.

But speaking to media at her weekly post-Cabinet press conference, Ardern said it was not something she would have ever done.

But she added that it was not for her to individually monitor the activities of every Minister when they travel overseas.

Earlier today, photos of Jones shooting a semi-automatic weapon were posted on Facebook by Jones' wife, Dot Jones.

A firearm expert confirmed to the Herald the gun Jones was shooting was an AR-15 – one of the guns banned in New Zealand after the March 15 terror attacks.

"Would I have done it? Absolutely not," Ardern said.

"But the most important thing for me is that that Minister [Jones] supports what this Government has done, and he does."

Jones, along with all NZ First MPs, voted in favour of the law which banned most semi-automatic weapons and high-capacity magazines in New Zealand earlier this year.

Ardern said that was much more important that what Jones gets up to when he is overseas.

"I only recall wholehearted and vocal support for what we have done – that hasn't changed."

She has not spoken to Jones about it, as she had only become aware of the situation soon before her 4pm post-Cabinet press conference.

Asked if she planned on speaking with him about the issue, she said: "I'm sure when I see him next I will raise it".

Asked about the photos, Jones told the Herald he was conducting "international research".

"The decisions that our Cabinet have made as to what types of arsenal are and are not legal is something I thoroughly agree with. We shouldn't be hosting them here," Jones said.

Asked about the photos, Regional Economic Development Minister Shane Jones told the Herald he was conducting "international research". Photo / Mark Mitchell

"I think I will regard my brief experience with said gun as part of international research … but I wouldn't catastrophise one photo."

Before he went on holiday roughly two weeks ago, Ardern asked Jones to take the Cabinet manual – the rulebook for Ministers – with him to refamiliarise himself with it.

Her comments came after Jones allegedly said forestry industry players needed to vote for him or they may miss out on the billions he's handing out for provincial growth.

Asked if Jones had taken her advice and refamiliarised himself with the Cabinet manual, Ardern said she would be following up on that when she talks to him about the firearm photos.