Simon Bridges insists he "didn't know" about a second $100,000 donation being investigated by the Serious Fraud Office (SFO).
The SFO filed criminal charges last month against four unnamed individuals in relation to donations paid into a National Party electorate bank account.
It was understood the charges related to a single $100,000 donation from a wealthy Chinese businessman. Former National MP Jami-Lee Ross alleged in 2018 that donation had been chopped up into smaller amounts to hide it from being declared.
But Auckland District Court documents show the charges relate to not just one but two donations to the National Party - one in June 2017 and another in June 2018.
The court charging documents released by Auckland District Court Judge Edwin Paul show three of the four individuals charged by the SFO face two charges of deception over the $100,000 donation in 2017.
All four defendents face charges of deception over a donation of $100,050 in 2018.
"I didn't know any of this," Bridges told reporters on Tuesday. "I have no information in relation to the other donation. I suppose someone does and presumably they've been charged.
"It's now before the courts and look, I just don't have information and can't speculate."
The court documents show the SFO alleges that, "the defendants adopted a fraudulent device, trick, or strategem whereby the 2018 Donation was split into sums of money less than $15,000, and transferred into the bank acocunts or eight different people, before being paid to, and retained by, the National Party".
The fourth individual is charged with the other defendants over the second 2018 donation, but is also facing one charge of providing misleading information to the SFO.
The defendants are scheduled to appear in the Auckland District Court on February 25. Judge Paul granted them interim name suppression on January 31.
Neither Simon Bridges nor any National MPs or board members have been charged by the SFO.
The Opposition leader said last month he had "no intention of keeping" the $100,000 donation at the centre of the SFO investigation and that he had written to the Electoral Commission to ask what to do with it.
Asked by a reporter on Tuesday if he would also return the second $100,000 donation, Bridges replied: "The problem is I don't know anything about it."
He added, "I think at the end of the day that's speculation. I don't know. I can tell you in relation to the donation that clearly I did know about it, that we've heard about."
The SFO launched an investigation in March 2019 into National Party donations after the police referred a complaint by now-independent MP Jami-Lee Ross who accused Bridges of fraud.
Ross said in October 2018 Bridges broke the law, alleging the Opposition leader had asked him to collect a $100,000 donation from Chinese businessman Zhang Yikun and not disclose it properly.
Ross said the donation arrived in eight amounts smaller than $15,000 - the threshold at which donations have to be declared by law - and that Bridges had stressed it should not be made public.
Ross released a recorded phone conversation between him and Bridges at the time, where he could be heard asking his then-leader what to do with the $100,000 donation.
Bridges has consistently denied any wrongdoing.
"I have always maintained I had nothing to do with the donations," Bridges said last month. "As I have always said the allegations against both myself and the party were baseless and false."
The SFO has announced it is also investigating the New Zealand First Foundation over allegations he New Zealand First Party was hiding donations through it.