• Deputy Prime Minister Barnaby Joyce during Question Time in the House of Representatives at Parliament House in Canberra, Thursday, February 15, 2018. (AAP)Source: AAP
Barnaby Joyce has resigned as the leader of the Nationals and deputy prime minister of Australia to sit on the government's backbench.
Paul Osborne

23 Feb 2018 - 1:42 PM  UPDATED 23 Feb 2018 - 3:28 PM

Barnaby Joyce will step down from the Nationals leadership, as his party investigates an allegation of sexual harassment he denies.

Mr Joyce told reporters in Armidale on Friday that he will throw open the leadership at a meeting in Canberra at 8am on Monday.

"To give these people in the weatherboard and iron, in those regional and small towns the best opportunity, this current cacophony of issues has to be put aside," Mr Joyce said.

The deputy prime minister has spent 16 days fighting off accusations of improper conduct over his affair with his now-pregnant former staffer Vikki Campion, and she was moved to two other political offices.

"Over the last half a month, there has been a litany of allegations. I don't believe any of them have been sustained," Mr Joyce said.

But he believes the government and his family needs a "circuit breaker" to stop the flood of stories.

"This has got to stop. It's not fair on them," he said.

He said the final straw was a sexual harassment allegation revealed on Thursday, which he has asked to be referred to the police.

Mr Joyce has not directly told Prime Minister Malcolm Turnbull he is resigning, but he said he spoke to Mathias Cormann, who is acting in the role while Mr Turnbull is overseas.

He also says he won't "snipe" from the back bench.

"I want to assist my colleagues, where I can, to keep their seats and also, quite naturally, in April, a baby will be born. I'll have other things on my mind," he said.

Mr Joyce said he would not be endorsing a replacement at Monday's party room meeting.

Three potential contenders are David Littleproud, David Gillespie and Michael McCormack.

With AAP