John Key says he has a "fun relationship" with staff at the Auckland cafe where he repeatedly pulled the hair of a waitress and that his actions were "a bit of banter."

Prime Minister John Key. Source: 1 NEWS

The Prime Minister spoke to ONE News Political Editor Corin Dann on a stopover at Los Angeles Airport this afternoon, en route to Gallipoli for Anzac centenary commemorations.

Mr Key says he accepts the hair pulling was not appropriate in hindsight, but that he thought the incident "was in context of practical jokes".

"It's a cafe I go to very regularly, I've been going there for years, we have a fun relationship," he said. "There's always lots of horsing around and sort of practical jokes and that's all there really was to it."

He said in hindsight his actions were not appropriate.

"But in the context of we have lots of fun and games there, there's always practical jokes and things," he said.

"It's a very warm, friendly relationship. In that context you'd say yes, but if you look at it now, no."

The unnamed waitress provided a detailed account of Mr Key's actions on the left-wing site The Daily Blog today and says they took place over a period of several weeks in 2014 in the build up to the election campaign.

She says she initially thought he was trying to be playful but as he kept pulling at her hair on subsequent visits, she was reduced to tears.

"He was like the school yard bully tugging on the little girl's hair trying to get a reaction, experiencing that feeling of power over her," she wrote.

"I would think to myself, even a five year old could tell you that if you pull on a girls' hair she will not like it, I shouldn't have to tell The Prime Minister that I don't like it when he pulls my hair."

The waitress felt Mr Key continued to target her even when her body language suggested she was very uncomfortable with the attention and that he would sometimes blame it on his wife Bronagh who was usually with him.

She alleges she told his accompanying security staff she was "sick of having my hair pulled and one day I'll snap and I'll punch him in the face".

Her account included a photo of two bottles of JK 2012 PM's Pinot Noir which she says he gave her in apology after she confronted him over his actions.

"At that point I realised she had actually taken offence cause it was all in the context of a bit of banter that was going on and so I obviously immediately apologised for that, gave her some wine," Mr Key added.

"She thanked me for that said 'that's all fine, no drama'."