The electoral donation complaint lodged by independent MP Jami-Lee Ross has been referred to the Serious Fraud Office.
A statement by the SFO said it had "received a referral from the police about a complaint they received in October last year in relation to the disclosure of political donations under the Electoral Act".
It does not refer to Mr Ross in the statement, however he lodged his complaint on October 17.
"The SFO does not disclose the detail of ongoing investigations to protect the integrity of the investigation and those involved," the statement said.
Mr Ross took the complaint against National leader Simon Bridges to police over a $100,000 donation, Mr Bridges has repeatedly denied all allegations.
Mr Bridges said it’s a matter for the National Party and "I expect them to co-operate”."
“There’s questions for the National Party and you should direct them to them”.
Mr Bridges says he hasn’t had any communication with police or the SFO and found out about it around 15 minutes prior to addressing media this morning.
Mr Ross this afternoon said "I have had a number of contacts with New Zealand police about that donation and other issues."
"I'm now pleased that the SFO is considering the issue."
Mr Bridges has repeatedly denied all allegations, and also said today he believed the complaint was against the National Party.
When asked about this, Mr Ross said, "In some point in time, Simon probably needs to realise he's the leader of the National Party, he sits on the party board, he's one of nine members."
Mr Ross said he understood there had been work done to track the money back through different bank accounts.
He said he was not concerned that he could be liable for prosecution, and said he did not break up the $100,000 donation himself.
"The Serious Fraud Office is the right organisation to be looking at this."
Mr Bridges denies asking Mr Ross to break up the donation from a wealthy Chinese businessman into smaller sums so it would remain anonymous.
Donations under $15,000 are below the disclosure threshold.