NZ First Leader Winston Peters is adamant that any potential probe by the Serious Fraud Office (SFO) into the NZ First Foundation's handling of donations will clear him, and his party.

In fact, speaking to reporters before heading into the House this afternoon, Peters predicted that the SFO won't even need to talk to him.

"Guess why?" he asked reporters before answering his own question: "I was not involved in any way, shape or form".

A spokesman for the SFO said this morning that it expected to receive a referral from police in relation to the New Zealand First Foundation and would be "assessing the matter".

This comes after questions were raised last year about how the Foundation handled donations.

The Electoral Commission said at the time it was looking into the matter.

Yesterday, it handed the probe over to the police – the police said it would be handing it over to the SFO.

This afternoon, Peters said he was pleased that the matter had been deferred to the police, then to the SFO.

But he said NZ First was going to wait and co-operate with the SFO to provide all the information.

"Until that report is in, I have exactly nothing more to say," he said.

• NZ First to review donations process after SFO invovlement

"But one thing," he continued.

"I'm not subject to any investigation here and nor, in that sense, is New Zealand First – so there is the end of it."

He said the SFO would not find any evidence of wrongdoing because no such evidence exists – "we have a legal opinion to back up what we have said".

"Our job is to co-operate to the fullest; I'm very confident of that and I expect other political parties to do the same as well."

Peters had previously asked NZ First to co-operate with the police over the alleged issued with the Foundation.

Peters was pressed as to whether this, in and of itself, was an admission of wrongdoing – he said it was not.

He said he asked the party to go to the police because: "You have all these rumours floating around, we needed to correct them".

He paralleled the Foundation saga today with some of the issues he had with the SFO in 2008.

Back then, Peters – then Minister of Foreign Affairs – stood aside as the SFO investigated issues to do with party donations.

The SFO said at the time it had no basis for fraud charges to be laid, but questions remained about possible breaches of electoral law over the non-disclosure of donations.

"When it was all over," he said this afternoon, "Winston Peters was utterly exonerated – those are the facts."

He said that would, indeed, again be the outcome of any potential SFO probe today.