Prime Minister John Key is tightening procedures in his office to ensure that he cannot be caught out again over his handling of the Government Communications Security Bureau.
Mr Key on Tuesday corrected in Parliament an answer he gave in September about when he knew of the bureau's involvement in monitoring internet entrepreneur Kim Dotcom.
Mr Key has said he first knew about it on 17 September this year, but briefing notes prepared for a visit he made to the GCSB on 29 February indicated that it was mentioned then.
Labour Party leader David Shearer also claims Mr Key brought it up when he spoke to GCSB staff and that a tape appears to have been made of the Prime Minister's comments.
The Prime Minister said Mr Shearer has misrepresented him. "He's made some wild accusations about GCSB which are plain wrong, and I reckon he'll never produce the tape."
Mr Key says he is making one staff member responsible for liaison with the GCSB. "I'm going to basically make sure we have a better handle on those things."
He said that as a general rule, speeches he gives are taped because there have been situations in the past where people have tried to misrepresent his views, as he says Mr Shearer has done.
But Mr Shearer said his party is simply asking questions and holding the Prime Minister to account over the matter.
"Whether or not a tape exists is actually not relevant. It's whether John Key talked about Kim Dotcom and GCSB at that staff meeting."
Labour MPs say they back Mr Shearer's handling of the Dotcom case even though he's unable to clearly say a tape exists.
Finance spokesperson David Parker says it's proper for Mr Shearer to question the Prime Minister about what he learned about the Dotcom investigation, and when.
Labour MP David Cunliffe says Mr Shearer has done what he thinks is the best thing for the caucus in taking the battle to the Prime Minister and that's a matter for his judgement.