The Queensland expert, Bob Katter, met with Scott Morrison and demanded tougher actions on the banks and the drought, warning that he could use his position of balance of power to cause "chaos" unless their concerns are addressed.
If the government loses the next by-election in the former Wentworth headquarters of Malcolm Turnbull, it could find itself relying on Mr. Katter to guarantee supply and confidence in the Lower House.
Katter told reporters that their demands were not a "quid pro quo", but left the door open to cause "chaos" if the Morrison government did not take action in key areas.
"I think the government, installed by the governor general, has the right to stability," Katter told reporters at the House of Parliament.
"But if the starvation of our first Australians continues, if the drought, which is imposed by the government because they will not [build dams] it continues, and if the banking investigation is not an adequate banking investigation, then it would have to think: why I do not interrupt? "
He said he could be willing to "cause chaos until we get a decent government in this country."
SBS News asked Mr. Katter how his demands were different than a quid pro quo.
"Look, if you want to call it a threat or not," said Mr. Katter.
"You can look at my story and you can say yes, of course, this guy has given each of these [prime ministers] a fair, and when he did not have a fair chance, then it was the time of chaos. "
Mr. Katter revealed that he met with the prime minister on Monday to discuss his concerns.
If the Liberals lose Wentworth, they will lose their majority of one seat in the House of Representatives.
Then they would need the three independents in the Chamber of Deputies, or four if they took Wentworth, to guarantee their authority to govern as a minority.
Independent Cathy McGowan said her "prevailing sentiment" was that the Coalition should be able to govern until the next election.
"Good government, make the ship turn, make its next six months, have an election and let people decide," McGowan told ABC Radio.
She said she would "renegotiate" with the prime minister after the result of the partial election was known.