McCormack vows 'I'm not challenging' as Nationals leadership speculation mounts

But he warned the party leadership against continuing "to blow the show up", urging a "pragmatic" approach to the Nationals' four core policies which prompted the spilt on May 20.

Party insiders acknowledge there is "dissatisfaction" with Queenslander Mr Littleproud's leadership after he announced the Coalition was breaking up, but potentially not enough to "recycle" former leaders like Mr McCormack.

One, though, described Mr Littleproud as a "dead man walking".

It's understood the 48-year-old, who was only re-elected party leader on May 12, is trying to shore up support for his position by offering shadow cabinet positions to Nationals MPs as reconciliation talks with the Liberal Party continue and appear closer to resolution.

Mr McCormack, who was deputy prime minister for three years from 2018 to 2021, said he was not re-seeking leadership despite speculation to the contrary.

"I'm not doing numbers," Mr McCormack, the Riverina MP, told ACM, the publisher of this masthead.

"I'm not challenging him."

But he did leave the door open.

He offered words of advice for Mr Littleproud, including allowing room to move on the four principles used to justify the break up with the Coalition in the first place.

These were nuclear power, big supermarket dominance, a $20 billion regional investment fund, and universal phone service.

Liberal MPs were expected to hold a virtual party room meeting at 1pm on May 23 to discuss the Nationals' policies, aiming for agreement to support lifting the moratorium on nuclear power, rather than committing to seven specific sites as the Coalition did during a disastrous election campaign.

The party room would also be discussing whether to support divestiture competition laws for the big supermarket chains as a "last resort".

"They've been four key policy areas that we've worked on for years, but I also think you need to be practical and pragmatic about this," Mr McCormack said.

"Obviously I'd like to get the band back together," he said.

"But I've done what I needed to do to broker peace arrangements and I'll do whatever is needed if I see that going pear shaped, but quite frankly, the path has been laid."

Mr McCormack emphasised his "strong standing relationship" with new Liberal leader Sussan Ley, who holds the neighbouring NSW seat of Farrer.

"If they want to win goodwill, go down that path and bring about a quick resolution to this.

"That'll be the mature and sensible thing to do.

"But if they want to continue to blow the show up, we'll be in opposition for longer than we otherwise would have."

As revealed by ACM, Mr McCormack was one of three Nationals MPs who disputed the split from the Liberal Party.

The other two were also long-serving parliamentarians - Barnaby Joyce and Darren Chester.