The image, produced by a political meme page and then shared by Andersen on her Instagram account, labelled an unfortunate fold in the monarch’s pants as “his kingussy”.
That’s a portmanteau of the words “king” and “p*ssy” and is meant to suggest the bunching of the King’s trousers resembled female anatomy.
Andersen, a senior Labour MP and former minister of the Crown, on Sunday apologised and removed the image, after questions from the Herald about its appropriateness.
Speaking to Newstalk ZB’s Nick Mills on Thursday, she said it was a “total mistake”.
“I just wasn’t thinking. I didn’t read it through fully before I shared it. That is absolutely no excuse and to be honest Nick, I was really disappointed in myself.”
Andersen agreed with Mills that King Charles III usually dresses immaculately.
“He does... I didn’t comment, I shared something else that someone else had said but commenting on appearances is not the appropriate thing for MPs to be doing. I should have fully read it and understood it before I shared it, but that is no excuse, it was bad behaviour indeed.”
Andersen said she wasn’t told off by party leadership, but the public spotlight on her doing “dumb stuff” was a “punishment in itself”.
“The first I realised was when I had a media inquiry from the Herald, and so I rang in and told them, so it went the other way, it was me putting my hand up, saying ‘hey, this has happened and it’s not ideal, I need to do something about it’.”
Political meme page @cindywithsign screenshotted the image – which had been shared by Luxon – and added a sign that said: “What I’m saying to you is that showing his king*ssy on main like that is just crazy [crying emoji]”.
Andersen, who first entered Parliament in 2017, served during the previous Labour Government in several positions, including the Justice Minister.
She is ranked ninth in the party.
King Charles was originally meant to visit Aotearoa during this year’s royal tour, which has seen the monarch spend time in Australia and visit Samoa for the CHOGM.