ACT's David Seymour reacts to Jacinda Ardern calling him 'arrogant prick' in Parliament

David Seymour says Prime Minister Jacinda Ardern's "arrogant prick" comment about him in Parliament is all water under the bridge.

A heated exchange in the House this week saw a rare slip from the Prime Minister, who was caught venting her frustration on a hot mic. 

The moment caught the attention of the world's media with the BBC, The Guardian, Daily Mail and even Cosmopolitan magazine reporting on the slip. 

But appearing on AM Early on Thursday, ACT Party leader Seymour said he didn't understand why the world's media was so interested.

"It's been a bit of a job to say, 'Look, at the end of the day she texted me, she said sorry, I said good on you, merry Christmas and that's just the end of it.' They don't seem to understand that [and] I say, 'Look, it's just the Kiwi way.'

"So, look, it's moved on," Seymour told host Nicky Styris.

However, Seymour described one way the incident had a "personal impact".

"My aunt texted me that night and she said, 'Look, I'm in Auckland, just got here, would you like to have dinner?' and I texted back [and] I said, 'Look, that would be really great but, sorry, I'm in Wellington. Anyway, why would you want to hang out with an arrogant prick like me?'

"Then she texts back: 'I'm sorry, I don't understand, what's this about?'... [It's] a good reminder that not everyone is following politics and they're sensible not to," Seymour joked.

When asked by Styris about whether he actually heard Ardern make the remarks, Seymour said he was alerted to them by a journalist via text.

"So I basically got up and asked the Speaker if he could find out if it was true, which is the normal thing to do, and it turned out it was."

Asked why he hadn't responded more harshly to Ardern's comments, Seymour said "I don't know why you would".

"It's been a helluva three years, everyone's tired - the last thing you need is more bickering among politicians so it wouldn't really be helping anyone."

Ardern issued a formal apology for her comments in Parliament on Wednesday. 

"I'm aware that comments I made in the House yesterday in regards to the leader of the ACT Party were recorded," she said. "On that basis, I wish to formally, in this House, withdraw and apologise for those comments, which I won't repeat."