FEDERAL Finance Minister Penny Wong has accused the opposition of hiding its plans to cut public spending if it wins government.

Senator Wong said on Thursday it was time for shadow treasurer Joe Hockey to be "up front" with Australians about any coalition plans to slash federal spending.

"Joe Hockey talks about a fiscal repair job but he's not prepared to tell Australians what choices he would make (and) what he would cut," Senator Wong told ABC radio, referring to Mr Hockey's comments in his budget reply speech on Wednesday.

"(Mr Hockey) and Tony Abbott are saying to Australians 'we're actually going to hide from you what our real plans are until after the election.'"

Senator Wong said coalition governments in Queensland and elsewhere had always "cut too hard and cut in the wrong places".

Mr Hockey used his budget reply on Wednesday to commit to fiscal repair, debt reduction and a return to surplus "as quickly as possible".

The coalition's small business spokesman Bruce Billson said an "emergency repair job" was needed on the federal budget.

"It is not only about the expenditure side," he told Sky News.

He said a report by the Bureau of Resources and Energy Economics, released on Wednesday, had estimated about $150 billion of resource projects had been delayed or cancelled since April 2012.

Small business had been "driven into a hole" by the government, he added.

"These are areas where we can restore the vitality of the economy, at the same time as being very prudent about expenditure and look to the future that's not mortgaging our kids," Mr Billson said.

But Assistant Treasurer David Bradbury said there is no budget crisis.

He questioned the opposition's commitment to keep all of the tax cuts and compensation associated with the carbon tax, while removing revenue source by abolishing the impost.

"How one earth do they expect to fund that?" he told Sky News.

"We are simply saying, tell us before the election."