Malcolm Turnbull’s call for Barnaby Joyce to consider his position may have backfired, with some Nationals digging in even more firmly behind their leader.

After the prime minister on Thursday launched a stinging criticism of Mr Joyce’s affair with a staffer, the Nationals leader hit back, calling the comments “inept” and “unnecessary”.

The deputy prime minister also told Mr Turnbull to butt out of National party politics after he was told to “consider his position”.

“There is nothing that we dislike more than implied intervention into the party processes of the National party,” Mr Joyce told reporters in Canberra on Friday.

“We are our own independent political unit – we make our own decisions, especially around those who are the office holders.”

AAP understands the pressure has only made some Nationals stand even more firmly behind Mr Joyce.

They believe none of the allegations of misuse of taxpayer funds have stuck and the scandal has become a media obsession.

Mr Joyce also said the pressure from Mr Turnbull about his leadership was having the opposite effect than the one he intended.

“It always does the same thing in the National party – and I’ve been around this organisation for over a couple of decades – it locks people in,” he said.

“They lock in behind the leader.”

Nationals MP Andrew Broad supports Mr Joyce but reserved the right to change his position on Joyce if evidence of impropriety comes to light.

“There’s been an error of judgment, there’s no doubt about that,” Mr Broad told ABC radio on Friday.

“But I’m still waiting to see if there’s been an abuse of power. If I see that and it’s clear, then I’ll be one of the people talking about what should be the action as a result of that.”

Agriculture Minister David Littleproud said Mr Joyce needed some time away after a “torrid” 10 days.

“Barnaby Joyce is still a human being. He has emotions. He has feelings,” Mr Littleproud told ABC radio.

“He needs his own time to able to recharge for his own wellbeing.”

Mr Joyce has been under fire for his affair with former staffer Vikki Campion, the jobs she was given in government offices, and his rent-free use of a townhouse belonging to a rich friend.