Prime Minister Bill English today revealed that Clutha-Southland MP Todd Barclay offered to play him the recording of his electorate agent's conversations last year.
English said he did not take up the offer.
Newsroom has also reported more detail today on a concerted bid by some local National members to prevent Barclay being reselected in December last year, an ultimately unsuccessful bid.
English made the admissions about being offered the recording at a press conference in Wellington following his speech to the National Party conference.
Barclay announced his resignation on Wednesday after publicly denying morning any recording on Tuesday.
The denial was in stark contrast to a Bill English text published by Newsroom, and in contrast to the police statement English released on Tuesday afternoon which said Barclay told him he had left his dictaphone running on the agent.
Sources sympathetic to Todd Barclay have been privately suggesting alternative theories to the commonly assumed one that Barclay recorded his agent to get proof that she had been bad-mouthing him.
One of the alternative theories is that Barclay only pretended to have a recording of her - which in itself would be sensational if it were true, given that she was paid an extra large amount from John Key's leader's fund as settlement for her privacy having been breached through the recording.
But English's admission that Barclay actually offered to play him the recording would tend to scotch the likelihood of the alternative theory being true.
Asked by a Newsroom reporter whether Barclay had offered to play English the recording, English said: "Did he offer to play me the recording? Ah, yes he did."
English also said he thought Barclay should cooperate with the police if it reopens the investigation, something Barclay refused to do last year.
"It would be my view he should cooperate," said English. "I respect his legal rights to make his own decisions about how he is represented and what action he takes."
Asked if he relayed that view to Barclay last year, that he should cooperate with the police inquiry, English said: "Yes I told him it was my view."
English cooperated with the police and gave an interview but according to the transcript released by English last week, the matter of the MP offering to play him the recording was not raised by the police interviewer nor volunteered by English.
Asked why he did not take up Barclay on the offer to listen to the recording, English said: "I just didn't think it was appropriate. There was an employment dispute going on for which I was not a party.
"In the context of employment disputes or police investigations, you don't want to make them worse with lose comments that could make them harder to resolve."
Later in the press conference, English refused to say whether he had advised Barclay to wipe the recording. The third time he was asked the question, he denied having done so.
English fuelled the recordings story at the weekend by suggesting five times in two television interviews that "the fact of the recordings has never actually been established."
Explaining those comment at the press conference, he said: "There has been an assumption that a criminal offence was committed."
He was not able to say what the police took into account in its investigation - which was closed with no charges being laid.
"I raised it in the context of an assumption that a criminal offence had been committed. That assumption simply isn't correct."
Newsroom is reporting today that concerned National Party members in Gore sent the National Party board at least nine letters in total outlining their concerns about Barclay.
One of the letters had been handed to President Peter Goodfellow at a pre-selection meeting in Balclutha. Newsroom reports that "Barclay had tried to denigrate English for his own means but didn't say how."
The Newsroom report goes on to detail how the former electorate chairman, Stuart Davie (to whom English initially sent the text about Barclay's recording) had raised his concerns with National southern board member Kate Hazlett who suggested he not stand again as chairman.
Davie had also received a "rark up" from board member Glenda Hughes, a former police officer, for giving the police his text message from Bill English.
Hughes is also understood to have asked the electorate agent, Glenys Dickson, to withdraw her complaint to the police about the recordings.
Dickson told Newsroom: "I was told if I didn't withdraw the police complaint I could potentially take down the National Party, and there was an inference that if National didn't have Barclay in Parliament, they were one short to pass legislation."
Dickson said she had been told that it would be difficult for her and her family if she had to appear in a high-profile court case.
"The board member explained to me if I withdrew my complaint I would be considered a hostile witness and the police would not have a case."
A subcommittee of the National Party rules committee headed by former cabinet minister Kate Wilkinson looked into complaints that the reselection had not been run properly and that Barclay's delegates were stacked.
Goodfellow said the inquiry did not uphold any of the complaints.
Commenting on the involvement of the board, English said at his press conference: "I wouldn't be surprised if in a national organisation with this employment dispute going on with, of course the local party involved in it, that the National board took an interest in it. It would irresponsible of them not to do that.
"There may be different interpretations as to what that amounted to and if there are serious allegations, well of course they should be dealt with by the appropriate authority."