National MP Joseph Mooney has publicly denied leaking a story to the media and has launched a blistering attack on broadcaster Mike Hosking, accusing him of breaching journalistic standards by airing allegations without seeking comment.

On Monday prime minister Christopher Luxon, in his weekly interview told Hosking said there were five MPs in the caucus he believed to be leaking to the media.

The following day Hosking named who he believed those MPs to be, including Mooney.

In a statement posted to social media, Mooney rejected any suggestion he had been behind a leak and said he was not aware of anyone else who had been.

“To be very clear, I did not leak a story to the media, nor do I know anyone else who did,” Mr Mooney said.

The MP took aim at what he described as “radio jocks seeking relevance” who, he said, rush to broadcast claims attributed to “impeccable sources” without approaching those named for comment.

“Who cares if you defame someone in the eyes of the nation without giving them a chance to respond first, as long as you get to breathlessly announce your so-called scoop that is in fact literally fake news,” he said.

Mooney said he expected higher standards from “an untrained student journalist working on the primary school newsletter on their first day,” and confirmed he intended to take the matter further.

“I am going to be making a complaint to the Media Council about this outrageous breach of journalistic standards,” he said.

The MP also issued a direct challenge to the broadcaster, inviting him to reveal the source of his reporting.

“I dare Mr Hosking to name his impeccable source, because I know for a fact that he is full of it,” Mr Mooney said.

Turning to matters inside the National caucus, Mooney sought to downplay any suggestion of internal division, saying colleagues had held productive talks and remained firmly behind the Prime Minister.

“We had a very good discussion yesterday. Our caucus is united behind the PM, as the confidence vote clearly showed,” he said. “We are 100 percent focused on serving Kiwis in this incredibly challenging time, and winning the upcoming election.”

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