Derryn Hinch says Barnaby Joyce “has to go” as leader of the National Party after his relationship with a staffer was made public.

He told Neil Mitchell the issue was now “open slather” for journalists and would not go away.

“They’ll go after every dollar he’s spent and try and match it up with his partner and see where and when they travelled, what they did etc.” Senator Hinch said on 3AW Mornings.

“The (Daily) Telegraph in Sydney has probably got a huge folder on Barnaby they’ve had for a long time and will just keep dropping stuff.

“They can’t go on us like this until the next election.

“He has to go.”

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