Labour is calling on the Prime Minister and the Government Communications Security Bureau to confirm whether an audio-visual recording exists of John Key addressing staff at the agency during his much publicised visit in February.

After initially denying knowledge of the spying scandal which has engulfed the Kim Dotcom trial, Key later admitted he was briefed over the case earlier this year but insisted he couldn't remember the conversation surrounding the spy agency’s role in the hearing.

But the opposition have questioned Key's claims, speculating whether a recording exists of Key's visit to the agency.

“Labour understands such a recording may exist and that it may show John Key referring to Kim Dotcom when speaking to staff," says David Shearer, Labour leader.

“There is one way to clear this up. The Prime Minister should give the green light to the agency to release any and all unclassified material about the visit and John Key’s comments to staff.

“It was during the visit on February 29 that the Prime Minister was briefed by GCSB about their surveillance of Kim Dotcom.

"He claims to have no memory of that. Previously though, he had told New Zealanders that he did not know about the surveillance till September 17.

“The agency’s review of its handling of the Dotcom case says that ‘no written record was kept of the meeting’. But it is silent on whether any audio-visual record exists of the Prime Minister’s visit.

“What New Zealanders need to know is what happened on that day when he visited GCSB, whether the Prime Minister’s comments were caught on tape and whether he mentioned Kim Dotcom to staff.

“It’s time for the full facts to be put on the table. This goes to the heart of John Key’s credibility and whether he’s telling the truth to New Zealanders.

“I’m calling on GCSB to confirm whether that audio-visual material still exists. If it simply shows John Key addressing staff then it should be publicly released because it is unlikely to contain classified information.

“At the very least, the material must be handed over to the relevant authorities who are looking into the case. I have also today made a request to the GCSB under the Official Information Act for any such material.

“There is now no alternative but to have a full, independent inquiry. A series of in-house investigations won’t cut it. There are too many unanswered questions.

"That is damaging our reputation for open and honest government and New Zealanders’ confidence in our intelligence agencies."

The Prime Minister ordered a full inquiry into the actions of the GCSB earlier this month, assigning inspector-general of Intelligence and Security Paul Neazor to investigate the allegations.