Allegations against the New Zealand First leader over a $100,000 donation have been referred by the Speaker of the House to Parliament's privileges committee.
Winston Peters did not declare on the register of pecuniary interests the donation from businessman Owen Glenn toward his legal fees in 2005.
After denying he had received any money from Mr Glenn, Mr Peters said he had been told by his lawyer that the businessman had contributed to a legal fund.
The Act Party leader Rodney Hide complained that Mr Peters had breached Parliament's rules by not declaring the money.
The Speaker, Margaret Wilson, says she referred the matter on because of the high level of public interest.
Ms Wilson says she has now determined the issue is a matter of privilege because it has implication for MPs and the reputation of Parliament. She says the committee needs to clarify what should be disclosed as a pecuniary interest.
Winston Peters says he welcomes the opportunity to meet Parliament's privileges committee to discuss the matters.
He says the committee will be able to see the facts set out in the clear light of day, and he would like the matter dealt with as soon as possible.