Prime Minister Scott Morrison is expected to unveil his new-look frontbench today, after the resignation of two Nationals Cabinet ministers in two days triggered a minor reshuffle.

Key points: Bridget McKenzie's role in the sports rorts scandal helped trigger the Cabinet reshuffle

Bridget McKenzie's role in the sports rorts scandal helped trigger the Cabinet reshuffle Senators McKenzie and Matt Canavan have stepped down from the frontbench

Senators McKenzie and Matt Canavan have stepped down from the frontbench Veterans Affairs Minister Darren Chester and Queensland MP Keith Pitt are tipped to return to Cabinet

Former Nationals deputy leader Bridget McKenzie resigned from the ministry on Sunday in an effort to stem the political damage over the sports grants saga

Outgoing Resources Minister Matt Canavan sensationally quit the frontbench the following day, in a bid to back Barnaby Joyce's ultimately unsuccessful attempt to wrest the Nationals leadership off Michael McCormack.

The newly elected deputy leader of the Nationals, David Littleproud, is expected to regain the agriculture portfolio, something he held before the election, while also retaining the drought and water portfolios.

That will bring the three key responsibilities back together under the same manager — they were separated after last year's election when Senator McKenzie took on agriculture.

Outspoken Queensland backbencher Keith Pitt, who failed in his bid to become deputy leader of the Nationals, is a frontrunner to be elevated to Cabinet.

Keith Pitt could be set to get a portfolio. ( ABC Wide Bay: Nicole Hegarty )

He is expected to inherit the resources and northern Australia portfolios vacated by Senator Canavan's surprise resignation.

However, he told AM he was waiting to find out who would be promoted.

"Everyone in the Nationals party room is always looking for more responsibility, and I think that's no surprise," Mr Pitt said.

"There's no expectations here — I'm obviously putting my hand up for additional responsibility, but so are all of my colleagues.

Veterans Affairs Minister Darren Chester, who currently sits in the outer ministry, is expected to return to Cabinet.

Veterans Affairs Minister Darren Chester is tipped for a return to Cabinet. ( ABC Gippsland: Sarah Maunder )

Sources have told the ABC he could take on Mr Littleproud's emergency management portfolio.

Mr Pitt and Mr Chester are both members of the House of Representatives and promoting them would mean no Nationals senators are in Cabinet.

The Nationals also appear unlikely to have any ministers in the Upper House. That means Liberal ministers would have to answer all questions about agriculture, drought, water and the other portfolios Nationals are in charge of.

It would also leave the Nationals without a woman in Cabinet, despite record levels of female representation achieved at the last election.

Despite losing their portfolios, Senator McKenzie will remain the leader in the Upper House, with Senator Canavan the deputy.

If there's to be a promotion in the Senate, Queenslander Susan McDonald, who was first elected last year, is tipped to receive it, most likely to the outer, or assistant, ministry ranks.

Mr Joyce has left open the prospect of another tilt at his party's top job, despite having released a statement on Tuesday that said the issue had been "finalised".

He told ABC Tamworth on Wednesday morning that there was a chance he could stand for the leadership again.

"People say never ever would you ever consider standing again [but] they can't do that because you just don't know what the circumstances are in the future," Mr Joyce said.

"But I'm glad that this issue's been dealt with, the boil's been lanced and we all move on."