Prime Minister John Key - who has known of Donghua Liu's claims of large donations to the Labour Party for some weeks - today said he was not aware of any suggestions Labour did not follow the rules with regard to any such payments.
His comment comes as Labour readies big legal guns for its defence in the event evidence of improper donations from Liu emerges.
Liu's claims of donations to Labour include a signed statement saying he paid close to $100,000 for wine at an auction fundraiser in 2007.
The Herald has also been told he paid $15,000 for a book signed by Helen Clark, Prime Minister at the time. Labour says it has so far been unable to find records of the donations.
Mr Key revealed yesterday that he had known of Liu's statement for some weeks.
However, this morning he said he had no information on whether the donations claimed by Liu had been handled improperly by Labour.
Labour President Moira Coatsworth has been among those including Labour Leader David Cunliffe and Mr Key calling for Mr Liu to put up evidence to substantiate his claims.
The party was being expected to investigate claims "that no evidence has been provided for."
What I've done is speak to a senior barrister. If there is evidence that is presented that we need to consider then we'll move but at the moment we have a completely unsubstantiated allegation.
Meanwhile, National Party President Peter Goodfellow once again refused to comment on whether National had received any donations from Liu other than the $22,000 disclosed in 2012.
Mr Goodfellow said that was a question for Liu.Mr Key said he had sought no assurances from Mr Goodfellow about any other donations by Liu to National.
"I am very confident that National acts within the law and is as transparent as it needs to be."