Former Speaker of the House Trevor Mallard is challenging resigned former Labour MP Dr Gaurav Sharma to release the full recording of a prior conversation between the pair which Mallard claims will prove Sharma breached privilege.

Sharma, who announced his shock resignation from Parliament on Tuesday, yesterday released a 54-second audio clip on social media of a conversation he'd had with Mallard about Sharma's request for an investigation into claims the former Hamilton West MP had made about staffers and Labour Party members.

In the recording, Sharma could be heard telling Mallard about written complaints he had made about staff members who didn't turn up to work or those who had arrived at work intoxicated.

"I'm at a point when I'm just hitting a stone wall," Sharma said to Mallard.

Mallard responded by saying he would ask Parliamentary Service chief executive Rafael Gonzalez-Montero to compile a report on the matter.

At the end of the clip, Mallard referenced the potential impact of making false claims against Labour colleagues.

"If it involved allegations against other party members then it will end up being career-limiting."

Sharma has previously claimed former party whip Kieran McAnulty had bullied him, a claim McAnulty had repeatedly denied.

In his post, Sharma criticised Mallard for not assisting him appropriately.

"I went to see Trevor Mallard because as the Speaker of the House, he was the minister responsible for Parliament but instead of supporting me or investigating the whole issue, he went straight to the Labour Party whips' office after my meeting with him, and told them that I had laid a complaint."

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Speaking to the NZ Herald, Mallard challenged Sharma to release the full recording of the conversation, which lasted about 30 minutes.

"I know [Sharma] won't [release] it because in it, he tells lies," Mallard said.

“I’m not at all surprised [he released the recording] and the idea that someone like that could cause me to lose any sleep is farcical.”

Asked for clarification concerning his "career-limiting" comment, Mallard said he meant to indicate to Sharma that his claims were "very serious" and if inaccurate, would be "career-limiting on someone, whatever happened".

Mallard also claimed the recording would prove what Sharma said in the House on the day of Speaker Adrian Rurawhe's confirmation in the role was untrue and a breach of privilege.

Sharma said he would happily provide the full audio to an independent investigator along with any other evidence he held.

"If they had carried out an independent investigation as I have repeatedly requested into the bullying I have been subjected to by the Labour whips, I wouldn't have to put this stuff on social media."

Rurawhe, a Labour MP, was nominated by the Government as the new Speaker in Parliament on August 24.

Sharma, then an independent MP after being expelled from Labour's caucus, said in the House it was refreshing to hear Rurawhe talk about "fairness", then claimed he spoke with Mallard two weeks ago about the issues he was facing and whether he could get legal support.

"But the Speaker said, 'Well if you raise anything about Labour colleagues and [they] challenge it, it would be the end of your career', and then the Speaker ended up going to the whip's office right after that to tell them that I had actually laid a complaint," Sharma said in the House

After this comment, Mallard could be heard saying, "liar".

As Sharma tried to continue, the new Speaker cut him off, saying Sharma's grievances were not fit to be debated in the House currently as it had only met for the purpose of electing the next Speaker.

Sharma's resignation has triggered a byelection in Hamilton West, which will take place on December 10.

Mallard gave his valedictory speech in Parliament yesterday afternoon as part of his farewell before taking up a diplomatic posting to the Republic of Ireland.

- by Adam Pearse, NZ Herald