"Multiple times the guy invited me to have a private dinner at his house and I thought 'that sounds dodgy' and never went...I have no idea what his intentions were."

Seymour said he received the invitation in 2018, adding: "I don't normally go to their house for dinner if I don't know them and we can't speak the same language - very unusual."

He said Zhang Yikun "made frequent appearances at various Chinese events on the calendar that a lot of MPs go to" and that he would usually have "several intermediaries standing around who would speak English".

Seymour said, "On multiple occasions he tried to get me to have dinner at his house, I said I won't do that, he said 'I own a restaurant and we could meet there', and I said that sounds worse.

"So, as a result I never had any kind of arranged meeting with the guy and I'm pleased about that."

Zhang Yikun has been charged by the SFO along with three others, including former National MP Jami-Lee Ross, Colin Zheng, Zhang's business partner and prospective National Party candidate; and Hengjia Zheng.

In 2018, Ross laid a complaint with police alleging National leader Simon Bridges had asked him to break up a $100,050 donation from Zhang because smaller sums under $15,000 would not have to be declared.

Bridges has always steadfastly denied the claims.

The charges against the four relate to not one, but two $100,000 donations, court documents seen by Newshub revealed. The 2018 donation, and another made in 2017 when Bill English was National leader and Prime Minister.

All four defendants face charges of deception over the 2018 donation.

Ross, Zhang and Colin Zheng face the same charge in relation to the 2017 donation. Hengjia Zheng does not but is also facing a charge of providing misleading information to the SFO.

The SFO is also currently investigating allegations the New Zealand First Party has been hiding donations through the New Zealand First Foundation.

Seymour said the amount of "sleaze in Wellington" is "unprecedented".

"Would I take seven donations of $15,000 contrived into un-declarable donations? Of course not, that's breaking the law - it's completely wrong," Seymour said.

"There's no problem with the laws we have. The law is very clear: to conspire to break the electoral law is a crime in itself and when you have seven donations of $15,000 then you are deliberately trying to break the law and that's completely wrong.

"I'm here to try and make the world a better place. I don't have time to lie awake at night wondering if our donations are above the law."

The Green Party is calling for a citizens' assembly to investigate public funding for political parties during election campaigns. New Zealand First is strongly against public funding of political party campaigns.

"We need to take this matter out of the hands of politicians and put into the hands of the people," Green Party co-leader James Shaw said.

"This is an issue in which parliamentarians are affected therefore it is difficult for them to come up with something that works. Why don't we kick it to the people?"

Seymour said Parliament is New Zealand's citizens' assembly.

"I know the Greens are in La La Land these days so they may not have noticed."