Nationals MP Barnaby Joyce has joked that his parliamentary colleagues miss him and want him back on the frontbench, as he relished a rare Question Time appearance.

His comments come as Nationals leader Michael McCormack faces the growing threat of a challenge amid concerns about his performance in the role.

Seeking to capitalise on the apparent instability, Labor used an obscure Parliamentary rule to direct a question at Mr Joyce, who sits on the backbench.

MPs cheered and applauded as the former deputy prime minister rose to his feet and proceeded to taunt his opponents.

"I must say I'm completely overwhelmed," he said.

"I know you find me endearing, I know you miss me, I know you want me back."

Earlier, Nationals frontbencher Michelle Landry conceded Mr Joyce was likely to become the party's leader again but insisted there is no appetite for change right now.

Hosing down speculation of an imminent challenge, Ms Landry said the Nationals were united behind Mr McCormack.

"You know, I'm sure at some stage in his career, Barnaby will be the leader again," Ms Landry told Sky News.

"The rest of my colleagues, and I've spoken to most of them, are happy for Michael to remain as leader.

"He has the support of our party room and we are not interested in having any leadership challenges."

Mr Joyce was forced to resign as leader in February after his affair with a former staffer became public, but he said this week that he would be open to returning to the top job if it was offered to him.

Some Nationals are unhappy with Mr McCormack's performance and are concerned about his appeal in Queensland, where One Nation is eroding the Coalition's voter base.

When he took over the top job, Mr McCormack was considered an unlikely leader but a safe pair of hands who would not attract controversy like his predecessor.

Sorry, this video has expired Nationals leader insists he has support of the party

Mr McCormack is remaining defiant though, declaring he has his colleagues' support.

"I know I've got the majority of the support of the party room," he told reporters in Canberra this morning.

"Not one member has come to me and said they're dissatisfied with anything.

"So I know I've got the support of the party room."

Several Nationals sources have told AM there are no immediate moves being made to unseat Mr McCormack, with one source predicting any challenge would be unlikely before December.

One source told AM only Ms Landry, Andrew Broad, Mark Coulton remain as core supporters for Mr McCormack, with more than two-thirds of the party room against him.

Littleproud, the heir apparent

Nationals MP David Littleproud argues he is not interested in leading the party. ( ABC News: Jed Cooper )

Agriculture Minister David Littleproud who is considered a strong media performer and a rising star of the party, has also ruled out any leadership ambitions.

"There's no chance of a leadership contest and even if there was, I am not interested in any leadership position," he said.

Tensions have been on the rise within the National Party over the introduction of a new agricultural visa, designed to fill labour shortages on farms.

Mr Littleproud was a strong backer of the policy but was understood to have been rebuffed by Prime Minister Scott Morrison.

This morning, Mr Morrison made it clear the visa was still on the table and, significantly, said Mr McCormack had been "critical" to the process.

Nationals MPs are keen to portray this latest speculation about a leadership challenge as a media beat-up.

Frontbencher Andrew Broad declared "the only people talking about it are the media."

"Michael McCormack is a fantastic leader, a decent, hard-working family man."

His ministerial colleague, Darren Chester, took aim at those "backgrounding" the media and said there was "a lot of smoke and hype to this but no substance".

"I think Michael, in many ways, is in the same vein as a John Anderson or a Mark Vaile," he said.

"A very steady, strong leader. I think that Michael's been doing a damn good job."