Labour Party leader Andrew Little has told Prime Minister John Key to "cut the crap" and apologise to New Zealanders over his office's links with the Security Intelligence Service (SIS).
The two have had a fiery exchange in Parliament during question time over a report which found Mr Key's staff helped right-wing blogger Cameron Slater request SIS briefing notes embarrassing to Phil Goff, when he was Labour leader in 2011.
The Inspector-General of Intelligence and Security Cheryl Gwyn's report is damning of the SIS, saying it released inaccurate and misleading information leading to unfounded criticism of Mr Goff.
She also found Mr Key's then deputy chief of staff, Phil de Joux, and a chief adviser, Jason Ede, encouraged blogger Cameron Slater to request the information about Mr Goff under the Official Information Act.
Despite that, Mr Key has claimed the report exonerates him and his office, and that parts of it are "highly contestable".
During question time today, Mr Little asked Mr Key what he found contestable about the report, particularly around the involvement of his staff.
"What does he contest about paragraph 218 which states that the second staffer provided SIS information to a blogger and that blogger then requested the information under the OIA while on the phone to his staffer," Mr Little said.
Mr Key said the blogger had disputed that.
"The point that's contested there is the point where Mr Slater emphasised that he had already decided to make the OIA request himself. That point is therefore contested," he said.
Mr Key then had a dig at Mr Goff's leaking parts of the report before it was publicly released, which Mr Goff admitted doing to Radio New Zealand.
Read the Inspector-General's full report - PDF 1.4MB
But Mr Little asked why Mr Key was showing contempt for the report and undermining Ms Gwyn's integrity.
Mr Key said the report did not find any indication of collusion and that the opposition was unhappy it did not fit its narrative, prompting an outburst from Mr Little.
"Why doesn't he cut the crap and just apologise to New Zealand for running a smear machine out of his office," he said.
Mr Key replied it was going to be an interesting three years and that he could not wait for the debates.
Slater texts PM
Mr Key was forced to return to Parliament late this afternoon to correct an answer he gave earlier in the day about the report.
In his corrected answer, Mr Key confirmed he exchanged text messages with Mr Slater about the report on Monday, the day before it was released.
"On Monday the 24th of November, I received an unsolicited text message from Mr Slater with a reference to the ... report," he said.
"There was a very short exchange where I briefly acknowledged that text message."
Earlier, Mr Key had denied having any contact with Mr Slater over the matter but later said he misunderstood the question; he had believed it related to the Chisholm inquiry, which had cleared former Justice Minister Judith Collins of allegations she had undermined the head of the Serious Fraud Office in 2011.
Meanwhile, Ms Gwyn said she was considering looking into the leak of the report.
"That disclosure was contrary to the non-disclosure obligations under which affected parties received some limited prior notice of the report and was also unfair to others," she said in a statement.
Ms Gwyn said that she was aware of Mr Goff's subsequent statements that he had disclosed some information concerning findings in the report, and that she would be seeking further information from Mr Goff and others.