Barnaby Joyce will challenge Michael McCormack for the leadership of the National Party if the position is spilled.
Nationals MPs will meet in Canberra on Tuesday to vote for a new deputy leader after Bridget McKenzie resigned over the sports rorts scandal.
“If there is a spill then I will put my hand up,” Mr Joyce told the Seven Network on Monday.
“I will leave that up to my colleagues. They can make the call.”
With Senator McKenzie stepping down as deputy there will be a ballot for her position, but it is up to the Nationals’ party room as to whether there is a spill for the leader’s position.
Leader Michael McCormack told the ABC he expected to retain his job – and said he had not heard from Mr Joyce.
“I’m sure Barnaby is ready to be the leader of the party should there be a spill called,” he said.
“But there has been no spill called. There is no vacancy for the leadership position.
“I am the leader of the party, I have the party support.”
Mr Joyce, who resigned as deputy prime minister in February 2018, talked up his record as Nationals leader.
“We had the maximum number of cabinet ministers we ever had, we won back more seats than we had in about 30 years, we delivered some big changes,” he said.
Resources Minister Matt Canavan is standing by Mr McCormack and will not be the one to call a spill.
“Of course I support Michael McCormack as leader of the National Party,” he said in Canberra on Monday.
Senator Canavan also confirmed he would not run for the deputy leadership. He is likely to replace Senator McKenzie as the Nationals leader in the Senate.
Water Minister David Littleproud appears to be a frontrunner to replace Senator McKenzie as deputy leader. NSW MP David Gillespie has also confirmed his candidacy for the role.
Michelle Landry, now the Nationals’ most senior woman, has ruled out running for the job. Darren Chester, who is yet to comment publicly on the issue, is another potential candidate for promotion.
Labor’s agriculture spokesman Joel Fitzgibbon relished the leadership rumblings on Monday.
“Barnaby Joyce just told us that the National Party is dysfunctional and, indeed, hopeless. My concern is that a dysfunctional government just got a whole lot more dysfunctional,” Mr Fitzgibbon said.
Mr McCormack will be acting agriculture minister until the Nationals leadership turmoil is resolved.