Breakfast host Hayley Holt's on air swearing slip up

On Wednesday morning Holt accidentally and dropped the f-bomb live on air.

The TVNZ Breakfast show host made the blunder when she tried to answer a question about how the size of a wave is measured. When she couldn't quite get the pronunciation, the word slipped out.

Holt was visibly shocked with her accidental swearing, covering her mouth and grabbing co-host John Campbell for support.

The moment passed without a hitch – that was until executive producer Jonathan Williams wandered on set.

Newsreader Jenny-May Coffin reassured Holt, telling her "you're human. It's okay."

Watch the video above for how the moment unfolded.

Last month Holt opened up about her sobriety journey, and said the decision to give up alcohol was 'the best decision ever'.