UPDATED 2.36PM: The acting Prime Minister can expect to face a few hair-raising questions while his boss is away on a trade mission in the Gulf States.

Labour is making it clear they will be asking questions about last week's revelations, that John Key repeatedly pulled the hair of Auckland waitress Amanda Bailey over a period of several months - even while his wife Bronagh was present. 

Labour Deputy Leader Annette King says they will be quizzing Deputy Prime Minister Bill English in John Key's absence, and eventually Key when he returns.

"He was there as the Prime Minister, and he will need to answer questions back home in New Zealand eventually."

King is unimpressed that Louise Upston has only acknowledged Key's behaviour, but not criticised it.

"I think she's responded appallingly. She hasn't responded at all."

But Upston isn't changing her position.

"There's the conversation around what the Prime Minister did. He's reflected and he's apologised, and I didn't have anything to add to that comment."