Scott Morrison is not a parliamentary majority, but can be formally relied on independent support by Bob Katter to make sure he can continue to manage.
On Thursday, the prime minister signed an agreement with Mr Ketter, who quenched the Queensland MP's questions of confidence and supply.
The government will finance up to $ 180 million for the Hughenden Irrigation Scheme and $ 54 million for the Hells Barrage.
"The agreement will support the government's continued stability and how we will continue to work," said Mr Morrison on Thursday.
"It will protect against political disturbances of the opposition."
The coalition lost its majority when Independent Kerrins Phelps got Malcolm Turnbull's old Wentworth site, leaving Morrison's unprotected majority.
"I am pleased with the proposals as set out in this letter," writes Mr Kets.
Mr. Katter is an irregular member during the weeks sitting.
© AAP 2018