Mr Hill said the premier had demonstrated his capacity to take tough decisions and to put personal allegiances aside.
"Being a leader is the most difficult job in any political structure and you have to do things which sometimes put your own desires to one side," he told reporters on Thursday.
"You've got to put the interests of the state first. Jay Weatherill I know will always do that.
"The public don't elect pussycats to be leaders, they want people who can get in there and make hard decisions."
Mr Hill will quit state cabinet from next Monday along with Transport and Infrastructure Minister Pat Conlon, the pair both heading to the backbench ahead of retiring from politics at the 2014 state election.
That has allowed Mr Weatherill to conduct a major cabinet reshuffle with speculation suggesting the premier might take on the added responsibility of treasurer while moving current Treasurer Jack Snelling to health.
Mr Hill said given the importance of economic and budgetary matters at present, it was understandable that Mr Weatherill might want to take on that role.
He dismissed suggestions that the workload might be too great for the premier.
"If it means he (Mr Weatherill) has to work harder, then I know he's prepared to do it," Mr Hill said.