Parliament Speaker Trevor Mallard slapped down MPs trying to find out more about his apology for calling a sacked Parliamentary worker a rapist.

Mallard has since said he wrongly used the term and in an out of court settlement has apologised to the man.

Act's David Seymour has told the Speaker the public has a right to know how much taxpayer money was spent.

Seymour said Mallard holds himself out as a Speaker who campaigns against bullying and harassment and he owes it to Parliament to give an explanation.

Mallard ordered him to take his seat and refused to take further questions.

He says the matter's been settled with an apology to the man and attempts to get him to elaborate about how much the defamation actions against him cost the taxpayer failed.

He refused any further discussion on it saying the matter was agreed late last week and he issued his statement as soon as was practical.

Listen to Neil Miller and Shane Te Pou discuss Mallard's future with Heather du Plessis-Allan above