Labour has continued to press for answers from National MP Pansy Wong about her use of taxpayer money, while criticising Prime Minister John Key over his handling of the situation.
Mrs Wong resigned from her ministerial portfolios on Friday after admitting her husband, Sammy, conducted personal business while on a taxpayer subsidised trip to China in late 2008.
Labour MP Pete Hodgson raised initial concerns about Mrs Wong signing a document between a China hovercraft company of which Mr Wong was a director, and a New Zealand-based hovercraft company. In the signing she made her ministerial credentials clear.
Mr Hodgson today released an extract from a Chinese local government website which discussed "minister" Mrs Wong's visit, while at the same time talking up the potential of the hovercraft business.
He has also raised questions about why businesses owned by Mr Wong were registered at Mrs Wong's Botany Downs electorate office.
Parliamentary rules are clear about the need to keep public and private interests separate and Labour has been putting pressure on Mr Key to get answers from Mrs Wong, who has taken a week of leave from Parliament.
A spokeswoman from Speaker Lockwood Smith's office said "all relevant matters" involving Mrs Wong would be investigated and a report was expected within three weeks. Mr Key said Mrs Wong shouldn't comment until she had read the report.
Mr Hodgson's criticism of Mr Key's handling of the situation extended to Parliament's debating chamber today, where he said the prime minister was developing a habit of denying, forgetting or minimising the seriousness of his MPs' indiscretions.
He brought up issues from last year including Finance Minister Bill English's questionable use of the ministerial housing allowance, and disgraced MP Richard Worth's mixing of private and public business.
MP Trevor Mallard joined in, asking if Mr Key stood by the "f...wit" comment his press secretary Kevin Taylor made about Mr Hodgson when he first questioned the appropriateness of Mrs Wong's signing of the hovercraft document.
Mr Key said Mr Taylor could have chosen his words more wisely.
"But the thing I'm relieved about is that he didn't use his fists," he said.
Mr Hodgson told reporters there was no reason why Mrs Wong couldn't talk about how many overseas trips her or her husband had taken, or give answers around companies attached to her electorate office.
"(Mr Key) is giving her advice to put her head down and just wait -- and that is not OK -- that's not the open, transparent government that he promises us..."
Mr Key said if Mrs Wong was still a minister, questions would need to be answered about any alleged promotion of business interests she undertook while in China. "But she is not a minister and I can't sack someone that has quit," he said.
Mr Hodgson said Mrs Wong's behaviour was "sad, and probably fatal" in terms of a future role in Cabinet.