Broadcasting Minister Trevor Mallard says a report from TVNZ on Tony Veitch's assault of his former partner does not tell him all he wants to know and he has asked for more information.
TVNZ, and Mr Veitch's other employer, the Radio Network, have admitted that senior executives have known some details of the incident since late last year.
Mr Mallard has asked the state broadcaster to provide further information about who was told, and how much they knew about the incident.
He says he has faith in TVNZ chairman Sir John Anderson and has spoken to him about the incident.
TVNZ says four managers discussed the matter with the sports broadcaster last December, but chose not to discipline him or inform the chief executive because the incident described was less severe than that reported in the media.
Mr Mallard says it is not a good look for the broadcaster.
Last week, Mr Veitch admitted he assaulted Kristin Dunne-Powell after an argument at their Auckland home in December 2006 and publicly apologised for his actions.
Mr Veitch said he and Ms Dunne-Powell had a confidentiality agreement, which included "payment for loss of income and distress I caused her".
Television New Zealand chief executive Rick Ellis said on Saturday that Mr Veitch sought advice from senior executives in December 2007 regarding the incident with Ms Dunne-Powell.
Mr Ellis said they were unaware of the details of the attack, but did know a bit later of a financial settlement.
On Friday, TVNZ announced that Mr Veitch would not present its coverage of the Olympic Games in Beijing.
Police have begun a formal investigation into the incident.
A company advertising on Mr Veitch's Radio Sport breakfast show is hinting it will withdraw its sponsorship if he is allowed back on air.
Vehicle Testing New Zealand says it will strongly consider cancelling its sponsorship of Mr Veitch's radio show if he returns.
The company's advertising contract is up for renewal at the end of the month.