Controversy over secret political funding is likely to be reignited by private emails that suggest Labour's biggest donor also gave money to NZ First.
The emails suggest repeated denials by Foreign Minister Winston Peters that his New Zealand First Party received a donation from businessman Owen Glenn appear to be incorrect.
A private email from Mr Glenn to his public relations man in New Zealand says he did give the party a donation.
Mr Peters was last night sticking by his story, saying through a spokesman that Mr Glenn had not given the party money - "he did not" - but he refused any other comment.
The conflicting stories raise credibility issues, as Mr Peters produced a large "NO" sign at a press conference soon after questions of a donation to his party arose.
Prime Minister Helen Clark refused to comment last night.
While she has sacked ministers for incorrect comments, they have been Labour ministers. She runs a minority Government, relying on New Zealand First in confidence and supply votes. With an election less than five months away, she would want to avoid any conflict with Mr Peters.
The email exchange between Mr Glenn and PR man Steve Fisher, managing director of Baldwin Boyle, occurred in February this year when the Monaco-based businessman was visiting New Zealand to open the Owen G. Glenn building at the Auckland University Business School.
Mr Fisher emailed Mr Glenn on February 21 about a Herald story on the businessman's donations to political parties. He was concerned that Mr Glenn and Mr Peters continued to give the same story.
Mr Glenn, in his reply to Mr Fisher, disclosed that he gave to the party.
Steve Fisher: Our plan worked well. There is nothing new about you in here Owen. Note that Winston says you have never made a donation to NZ First, so at all costs you must stick to that line. It was definitely the right thing to do to deny the Maori party offer as well.
Owen Glenn: Steve - are you saying I should deny giving a donation to NZ First?? When I did?
Steve Fisher: No, just stick to the line of referring stuff to NZ First. What I'm saying is we don't want to contradict Winston.
Last night, Mr Glenn was in Monaco, and when asked why he had not said in February that he gave money, he said: "I made a decision not to say anything to anybody because there was so much controversy about everything. I was just there to open the business school so I just didn't want to get caught up in anything ... I elected not to say anything."
He also expressed disappointment at the fuss made over his political donations, saying: "I just don't find New Zealand a very friendly place and it's unlikely I will go back."
When Mr Glenn was in New Zealand in February, he also said he was hoping to be appointed the country's honorary consul in Monaco - a decision that would have been made by Mr Peters as Foreign Minister.
Dail Jones, NZ First party president at the time and now a list MP, fuelled speculation of a donation to his party when he told the Herald during Mr Glenn's visit that a large anonymous donation - "closer to $100,000" than $10,000 - had appeared in the party's accounts last December.
But Mr Peters said the money was an aggregation of smaller donations.