Sharma, who will be invited to address the caucus at tomorrow morning's meeting ahead of a vote on whether to expel him, sent The New Zealand Herald a screengrab of what he says is a message from Cabinet Minister Kiri Allan sent in February to a group chat that included all MPs, Prime Minister Jacinda Ardern and some senior members of the party.
Asked in what context the message was sent, Sharma said it was a one-off message without a discussion on the topic before or after it was sent.
Sharma claimed the message contradicted Ardern's recent comments about how her Government was committed to honouring the spirit of the Official Information Act (OIA).
"There is a problem here with accountability, with transparency," Sharma told the Herald.
Sharma was suspended from the caucus last week after making a string of public statements alleging bullying by Labour's whips over staffing management issues.
He was warned that he would be expelled if he continued his attacks.
"Hey team - reminder to have a chat with your ministerial colleague before sending correspondence.
"All correspondence is OIA-able and if we are being lobbied on issues by colleagues, especially where we haven't had a yarn, things unfolding through OIA process less then desirable [sic].
We are a team, you can talk to us directly (read: should talk to us directly before sending letters). Cheers!"
The move to a vote on expulsion came after Sharma released a recording of a conversation he had with another Labour MP about a secret meeting of the rest of the caucus last Monday night.
Over the weekend, Sharma also did several more media interviews, including claiming that MPs were being coached on how to get around the requirements of the OIA.
He has repeatedly called for an investigation into the claims he made about staff, his treatment by the party, and into the claims against him - but Ardern has said there is not sufficient evidence to warrant such a probe.
Sharma had not taken part in last week's online meeting in which he was suspended by a unanimous vote, saying later that was because of his concerns the outcome had been pre-determined in a secret meeting the Labour MPs had about him the night before.
A spokesperson for Ardern has confirmed Sharma will be invited to address the caucus at tomorrow morning's meeting ahead of a vote on whether to expel him - although Sharma told the Herald today that he did not know whether he was expected to attend the meeting - or whether he would take part if he was invited to attend.
Asked in what context the message was sent, Sharma said it was a one-off message without a discussion on the topic before or after it was sent.
PM addresses Sharma screengrab
Ardern said Allan could not be seen as if she was being influenced by lobbying from an MP.
"There's nothing inappropriate about reminding MPs about that. We take our job seriously, We can be judicially reviewed on the basis we make those decisions."
She said it was important to be sure other MPs also knew what was appropriate and what was not.
Allan was Minister of Conservation at the time of the message.
Ardern said the Allan message was not aimed at evading the OIA by holding verbal conversations rather than writing letters - but to give a minister the chance to tell an MP if the lobbying they were planning would compromise the minister's decision-making ability.
Sharma explusion 'a decision for caucus'
Ardern would not say it was certain Sharma would be expelled after caucus meets tomorrow.
"It's a decision for caucus."
Sharma would be given the opportunity to attend and speak, Ardern said. However, until now Sharma had not taken part in previous meetings or in the independent mediation she had proposed.
The Prime Minister ruled out holding another pre-caucus meeting of the MPs, saying that had been partly because MPs had not faced such a process before and it was to explain how it worked and what the options were.
Ardern said there had been no basis to the claims Sharma had made and there should be a threshold before a formal inquiry was called because of its cost and strain on those involved.
"I don't want to get into a tit for tat over a secret recording" when asked if she was going to try to find the other MP in a phone call recording with Sharma revealed to Newshub last week.
She believed that MP could have been trying to help Sharma.
Ardern said what Sharma had portrayed about the briefings on the Official Information Act had "completely misrepresented" the nature of those briefings.
She said they had not yet considered whether to invoke the waka jumping law in the event Sharma was expelled from caucus, saying the cost of a byelection was one issue at the top of her mind.
Asked if special measures were taken to support the Labour group of 2020, given its size, Robertson and Ardern said there was a buddy system and MPs could go to deputy leader Kelvin Davis or Ardern herself for talks.
Robertson said there was more support for new MPs now than there had been when they entered Parliament.
Asked how she was feeling personally about the claims Sharma had made, the Prime Minister said the thing she found most disappointing was the claims Sharma had made about other MPs who she knew were working hard and capable.
She said she could not reconcile the things Sharma had said with what she knew of those people. She it was sad it had happened "but I'm also sad for those who have been attacked".
The heart of the issue was not Sharma's initial public statement but the conduct after that point - including Sharma's refusal to take part in any efforts to sort the problem out - she said.
