The Prime Minister says he “cannot recall” when he first knew about Barnaby Joyce’s affair with his staffer, Vikki Campion.

And he has given another rogue Nationals MP a rap across the knuckles, calling George Christensen’s recent social media post “inappropriate”.

Responding to Neil Mitchell’s questions about when the PM was first notified of the Joyce/Campion affair, Mr Turnbull said he didn’t know.

“Barnaby at no time said to me that he was in a sexual relationship with this woman, Vikki Campion,” Mr Turnbull said.

“He never made that admission to me.

“I cannot recall when I first heard a rumour about it but probably, you know, about the same time, possibly later than others. Parliament house, as you would also know, is full of rumours.”

NEIL: You didn’t consider asking?

PM: I’m not going to go into the private discussion I’ve had with him.

NEIL: Were you misled?

PM: I’m not going to go into those discussions Neil. It’s important that I am able to have confidential discussions with ministers about sensitive matters.

NEIL: Do you trust him?

PM: I do, of course I do.

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The PM also tried to refrain from being drawn into speculation about Nationals MP George Christensen’s recent Facebook post.

The photo showed Christensen holding a handgun, accompanied by the caption, “You gotta ask yourself, do you feel lucky, greenie punks?”

Amid growing backlash online, Christensen changed the caption to, “Do you have a sense of humour, greenie punks?”, before eventually deleting the image.

“It was very inappropriate, there’s been a referral to the Australian Federal Police,” Mr Turnbull said.

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