United Future leader Peter Dunne denies a donation received by his party was linked to his stance on international fishing restrictions.
The Dominion Post says United Future received $5000 after Mr Dunne made a public statement opposing the United Nations legislation in 1999.
That statement followed a meeting Mr Dunne had with Ross Meurant, who was acting as a broker for the Vela family.
But Mr Dunne told Morning Report that although he met Mr Meurant and subsequently made the statement, the donation had nothing to do with it.
He confirmed the donation was around $5000.
Labour leader Helen Clark says she hopes National will be asking as many questions of Peter Dunne over political donations as it does of Winston Peters.
Talking to workers at a West Auckland factory, Miss Clark described the newspaper story as "fishy".
United Future has pledged its support to National, ruling out working with Labour after the election.