SHADOW treasurer Joe Hockey today stumbled over claims he miscalculated spending savings, simply saying they were right "at a point of time''.

Mr Hockey declined to acknowledge what appear to be double-counting of cuts and said firmly: "We stand by our numbers.''

He bristled when queried about his calculations during an address to the National Press Club in Canberra, replying to last week's Budget.

However, Mr Hockey did not directly counter the claims and was left looking embarrassed and unable to respond.

The issue is important as the Opposition has said it would be able to return the Budget to a surplus early by imposing tougher cuts on spending, and has accused the Government of not being vigorously enough in the economic statement released last Tuesday.

A reporter put to Mr Hockey that part of the $52 billion the Coalition had said it would cut from spending included $1.7 billion from Labor's proposed company tax cuts, which were to be funded by a higher mining tax.



However, the Coalition would not proceed with the mining tax so the saving was "illusory''.

Second, the Coalition would increase tax on large companies by 1.7 per cent to cover a paid parental leave scheme, but then proposed a 1.5 per cent cut in company tax to be funded by a freeze on public service recruitment.



However, that saving had already been allocated to the Coalition's Direct Action plans on climate change.

Third, the Coalition's a claimed public service blow-out of 20,000 staff since 2007 included a boost in military and reservist numbers.

"Our numbers stack up. Our $52 billion stack up from last year( during the election campaign),'' said Mr Hockey.

"You could have asked that question any time over the last 12 months if you thought there was double counting. Our numbers are accurate and we stand by those numbers at a point of time.''

Part of Mr Hockey's problem was that the Opposition has imposed a rigid policy of concentrating exclusively on Government economic policy without offering any alternatives of their own.



This limits the shadow treasurer's participation in the Budget debate.

However, he strongly question's the economic credibility of the Budget and underlined previously announced Coalition policies.

Mr Hockey said a Coalition in government would make the long overdue step of reducing housing costs, which were among te highest in the world.

"The Australian dream of owning your own home is fast becoming a financial nightmare,'' he said. "And a big impediment to building more housing is Australia's poor regulatory environment.''

He pledged "critical'' reform of construction industry regulation and planning to "address te housing affordability crisis''.

Mr Hockey said middle Australia was angry because the Government was making the transition to the resources boom economy more difficult.

"The annual pre-Budget rhetoric about a `tough Budget' made people even angrier,'' he told the NPC.

"It reminded Australians of of the waste by this Labor Government in Pink Batts, school halls, solar panels, and $900 cheques that they and their children will now have to pay off.''