Jami-Lee Ross, the party's former chief whip, was named as one-of-four men facing charges laid by the Serious Fraud Office accused of using a "fraudulent device, trick, or stratagem" in accepting donations.

The others are businessmen Yikun Zhang, Colin Zheng and Joe Zheng, each of whom had their name suppression lifted by the Auckland District Court on Wednesday.

They face maximum jail terms of up to seven years.

In 2018, the Botany MP referred a $100,000 donation to police, claiming it proved corruption on the part of Mr Bridges, and that he was asked to receive the bumper donation through a back-door foundation.

Around the same time, Mr Ross was unanimously voted out of the National Party amid accusations of leaking damaging information about Mr Bridges.

Mr Ross will fight the charges and maintains he is a "fall guy" for the National Party leadership.

"The donations that led me to blow the whistle were offered to Mr Bridges, not me. They were not for my own political or personal use. They improved Mr Bridges' position, not mine," he said.

Lawyers for the three businessmen also issued a statement, saying their clients are "proud New Zealanders and philanthropists".

"They were urged to follow a process and are now deeply disappointed at being caught up in a donations fiasco," the statement read.

Mr Bridges has said Mr Ross was a "disgruntled former MP" with a "vendetta".

This development is the latest in a rolling saga that has engulfed New Zealand politics for two years.

The foundation linked to Deputy Prime Minister Winston Peters' party is also being investigated by the Serious Fraud Office, as the Electoral Commission believes it has failed to declare donations.

Mr Peters has refused questions on the matter all week.

Australian Associated Press