The Prime Minister has received an assurance from the New Zealand First Party that it has not received a donation from Owen Glenn.
Winston Peters says the party has never received money from the Monaco-based expatriate businessman, who has asked to be New Zealand's honorary consul there.
Earlier this week, The New Zealand Herald reported Mr Glenn admitted in an email to a public relations consultant making a donation to New Zealand First.
A spokesperson for the Prime Minister says Mr Peters - who is also the Foreign Affairs Minister - has given Miss Clark the same assurances he has made publicly.
Despite Mr Glenn's desire to become New Zealand's honourary counsul in Monaco, Miss Clark says that is unlikely.