"In fact I would be breaching my own ethical boundaries and, I believe, further damage relations between RNZ, the Minister and the wider Government, which is an integral part of the framework within which we work, if I complied with the request."
Griffin was asked for the voicemail and other communications when he and RNZ chief executive Paul Thompson were called back to the select committee last week to correct the record over comments they made previously about the nature of a meeting between RNZ's former head of content Carol Hirschfeld and Curran.
In his letter, Griffin said that from his perspective he reappeared before the committee "solely to apologise for unknowingly misleading the committee at the earlier meeting and to explain how that had occurred. I appeared in person for the reasons I outlined to the committee.
"In making this decision I have also taken into account my belief that it is unusual for a select committee to request personal communications from a minister to the head of a crown entity. To achieve finality at this time, I respectfully decline the request by the committee."
The select committee met this morning to review last week's hearing but Young declined to comment on what was discussed or whether further action would be taken to compel Griffin to turn over the recording.
The voicemail is central to determining whose account, Curran's or Griffin's, is correct about advice she gave him.
The recording either reveals Curran tried to persuade Griffin not to appear, as he has suggested, or that she was passing on advice that he need not appear in person if he was not able and a letter would suffice.
Hirschfeld was forced to resign after repeatedly lying to her bosses over a meeting she had with Curran in December. She had said it was a chance encounter but Curran later said it had been diaried.
The pair met at Wellington's Astoria café but the substance of what they discussed has not been revealed.