Prime Minister declines to offer evidence to back his claim he was mischaracterised in emails

Prime Minister Christopher Luxon has declined to offer any evidence to back his side of a conflict with his foreign minister's office, saying he has "nothing more to add".

In an interview with RNZ on Friday, Luxon stood firm: "I've just told you my side of the story. It's in the statement."

Luxon's statement - issued on Thursday - claimed a bombshell document release from Winston Peters' office had "mischaracterised" Luxon's position on the war in Iran.

The published emails - from early March - showed Peters' team pushing back against the Prime Minister's "preference for more explicit public support" of the US-led airstrikes.

But in his first media interview on the topic, Luxon denied that had been his "preference" at the time.

He told RNZ he had simply been testing New Zealand's position - which was to "acknowledge" the strikes - against that of Australia and Canada, which had used the word "support".

"I challenge the advice I receive," Luxon said. "I'm pro-New Zealand, not pro-US."

Luxon said, ultimately, all public government statements reflected his view and would not be issued otherwise: "It's as simple as that."

"I'm the prime minister of New Zealand," he said. "It's quite right that I test our position versus others... And what we came out with, I fully support. That's exactly what I believe... otherwise it wouldn't have been said."

When releasing the documents to media, a spokesperson for Peters added that Luxon's suggested course of action had been "imprudent" and "counter to New Zealand's national interests".

Peters has not retracted that remark, nor responded to the claims of mischaracterisation, though he has admitted it was a "mistake" not to consult Luxon before releasing the emails.

RNZ lodged a request with Luxon's office for any documentation which might prove that Peters' office got the PM's position wrong.

Asked directly whether he'd release such evidence, Luxon said he had already laid out his version of events.

"I've really got nothing more to add."

Luxon's Thursday statement also included his strongest criticism yet of Peters, questioning both his judgement and motives.

"The decision to release these discussions to the media clearly put politics ahead of the national interest," the statement said.

Asked whether Peters therefore remained fit for his role as foreign minister, Luxon repeatedly refused to engage.

"I'm just not getting into it," Luxon told RNZ. "I've said everything I want to say about it."

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