A former New Zealand First deputy leader still has questions around donations made to the Party's Foundation.

They are now being investigating by the Serious Fraud Office after the Electoral Commission referred its findings to police.

Peter Brown told Mike Hosking he had assumed everything at the Foundation would be above board.

"The foundation is being run by Brian Henry QC, who is also a personal friend of Winston Peters, along with Doug Woolerton - the founding President of New Zealand First."

Political commentator Ben Thomas told Mike Hosking history might repeat.

"The last time the National Party ruled out working with NZ First they spent the election campaign embroiled in an SFO investigation about the donatations, they were turfed out of Parliament."

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