OUTSPOKEN Nationals MP Barnaby Joyce has threatened to break up the Coalition in the wake of the Liberals’ leadership crisis.

In an extraordinary interview with his local paper, The Northern Daily Leader, the Agriculture Minister and Nationals deputy leader said the country party’s support to the Liberals was not unconditional.

“What I say to my colleagues in the Liberal party is this: we didn’t want this. We gave you fair warning,” Mr Joyce said.

“Do not consider that the National party support is without question.

“If all of a sudden a different person is walking down the aisle towards us, don’t necessarily think the wedding is still on.”

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In a rapid escalation of the Liberals’ leadership crisis this afternoon, West Australian Liberals Luke Simpkins and Don Randall have called for a spill on Tuesday.

Mr Simpkins said that he had brought forward the spill motion because he believed he was “doing the right thing for the country”.

No Liberal MP has yet put their hand up to challenge Tony Abbott for the prime ministership.

News.com.au contacted Mr Joyce’s office for further comment, but a spokesman said he would not be giving any further media interviews this afternoon.

There appears to be a split between Mr Joyce and Nationals leader Warren Truss, who has reiterated the party’s wish for a “strong, stable and unified Coalition government to take the country forward”.

Mr Joyce told the Leaderthat he was “extremely disappointed” by the leadership crisis.

“We do not condone chaos. That’s what the Australian people voted against at the last election,” he said.