The Electoral Commission will on Monday discuss New Zealand First's donation returns, following disclosures of large contributions from a Trust.
The Spencer Trust has confirmed it made donations to the party and paid its bills, worth more than $10,000, in 2005, 2006 and 2007.
Any donation over that amount should have been declared but New Zealand First made nil-returns for all three years.
The Electoral Commission says it will consider formal correspondence from the president of the party on Monday afternoon, and options for possible further action.
The police have also been asked to investigate New Zealand First's 2007 return by the ACT party leader, Rodney Hide.
Parliament's Privileges Committee will on Tuesday hear directly from offshore businessman Owen Glenn, who donated $100,000 towards the legal costs of an electroral petition in Tauranga by Winston Peters in 2006.
Mr Peters appeared before the committee on Thursday, but gave no evidence.