Treasurer Wayne Swan will today promise to release the 2012-13 budget outcome “well before the election”, as part of measures to increase budget transparency and put pressure on the opposition over costings.

Speaking to the Australian Business Economists in Sydney, Mr Swan will commit to giving more funds to the recently established Parliamentary Budget Office.

“This will enhance the capacity for costings to be prepared in the lead up to the election, removing any excuse for policies to be released like thought balloons rather than rigorously costed policies,” he says in his speech.

The opposition has been using the PBO to cost many of its policies.

Mr Swan also says the government will introduce legislation for the PBO to prepare a post election audit of all political parties, publishing full costings of their election commitments and budget bottom line. This would come out 30 days after an election.

“This will remove the capacity of any political party to try and mislead the Australian people and punish those that do.

"It will avoid a situation we saw last election, where the Liberal party thought they could con the Australian people… Their $11 billion black hole in the budget bottom line would have been uncovered, regardless of the election outcome.”

Mr Swan will also commit to releasing the budget outcome as soon as the secretaries of the departments of Treasury and Finance inform the government they have a reliable figure.

Treasury and Finance officials have been clear that a reliable estimate could be made “well before the election and we commit to releasing them.”

“This means that the 2012-13 outcome of the underlying cash balance - the most important budget aggregate - will be there for everyone to see.”

Under the present arrangements, this figure does not have to come out until well into the formal campaign.

Mr Swan will repeat that the government needs to do more to ensure the budget is sustainable over time.

“Our focus will be on ensuring the sustainability of priority spending, and improving the integrity of the tax system.

"Inevitably, these reforms will involve very difficult decisions, but they will always be guided by our Labor values.”

New spending will be offset by savings, and real spending growth will average no more than two percent growth over the forward estimates. The government will also keep tax as a share of GDP, on average, below the 2007-08 level of 23.7 percent.