Unions critical of proposed SA budget cuts

Union bosses have slammed the South Australian mid-year budget review saying proposed spending cuts in the public sector are unrealistic.

Up to $370 million will be cut from government agencies over the next four years as it looks to recoup projected revenue from its failed bank tax.

Back-office jobs will go, but Treasurer Tom Koutsantonis says no frontline workers, including nurses, doctors, teachers and police, will be axed.

"We simply cannot believe, find or fathom that there is $370 million worth of services or jobs being delivered currently in our public sector which are essentially beyond requirements," SA Unions secretary Joe Szakacs told ABC radio on Friday.

"There is absolutely not the room for $370 million worth of jobs and service cut."

But the South Australian government has defended its decision as it strives to keep the state's finances on track.

"What we have done is excluded all frontline services, so there will be no change whatsoever to anything the public touches or sees," Mr Kousantonis said.

The treasurer handed down the state's mid-year budget review on Thursday, revealing a surplus of $443 million for 2016/17 but said savings were needed to offset the loss of revenue from the proposed bank tax, which was voted down in state parliament.

The Liberal opposition has criticised the review for again failing to ease cost-of-living pressures while Business SA has questioned the government's ability to deliver its proposed savings.