Former Labour Party staffer Phil Quin - the man who accused Greens MP Golriz Ghahraman of "genocide denial" and then withdrew the claim - has refuted claims that he ran a PR campaign for Rwandan President Paul Kagame.

And he has expressed regret for the public furore that resulted from his Twitter outburst against Ms Ghahraman.

Over the past two weeks, New Zealand's first refugee MP has had to answer a series of attacks against her credibility, including her exact role with the United Nations war crimes tribunals in Rwanda.

Ms Ghahraman was forced to change her Green Party website profile, which alluded to "putting on trial world leaders for abusing their power", without mentioning that she had actually worked on the defence staff for several accused of those crimes.

Mr Quin, who worked for the Rwandan government as a communications consultant at that time, was one of her strongest accusers, tweeting that she was a "straightforward genocide denier" and hinting she would not be in Parliament very long.

This week, he has faced attacks on his own integrity, through an anonymous Reddit post that suggests he waged a public relations campaign on behalf of Rwandan President Paul Kagame, whom some civil rights groups had suspected of war crimes that were never brought to trial.

In an exclusive interview with Newshub, Mr Quin insists he never intended to publicly attack Ms Ghahraman and wasn't part of an orchestrated smear campaign against her.

"Somebody has obviously spent an hour on Google, I guess," he says, about the Reddit post. "It's an extremely shallow hatchet job, which is fine - people were annoyed with me and wanted to get some payback.

"It's completely untrue. From 2012-15, I worked in Rwanda on a project funded by the EU on capacity-building in the public sector. It had nothing to do with any of the stuff in that article.

"I worked for a tiny corner of a very small part of a very large government - they wouldn't listen to me and I wouldn't be arrogant enough to give them that kind of advice.