The Gillard Government will force political parties to submit all election promises for independent costing before the September Federal election.
The move is designed to ramp up pressure on Tony Abbott to reveal the true cost of his policies.
But the results of the analyses will not be released until 30 days after the election.
In a speech today, Treasurer Wayne Swan will also reveal the Government has lost at least $4 billion in revenue since its mid-year update and that the next Budget will have wide changes aimed to safeguard tax receipts.
The state of the Budget and the cost of policies are looming as key parts of the September 14 election campaigns.
The Opposition has signalled it will not release costed policies until after Treasury's pre-election Budget report that has to be published by August 22.
However, the Government believes the Opposition will not release all of its costed policies in a re-run of the events before the 2010 election.
Mr Swan will tell an Australian Business Economists function that a repeat of any political party sitting on its policies will not occur again.
The independent Parliamentary Budget Office will audit all political party policies and make the results public within 30 days after the election.
The Treasurer says there will be no hiding for any party from its election promises.
"This will remove the capacity of any party to try to mislead the Australian people and punish those that do," he will say.
The change, including extra funding for the PBO, will go before Parliament within weeks.
Mr Swan will confirm that the outcome of the 2012-13 Budget, which was unlikely to be known before September 14, will be made public before the election.
He will use his speech to argue revenue writedowns have continued, forcing deeper cuts in spending to make space for the Government's priorities.
The tax to GDP ratio is now expected to fall below 22 per cent again, suggesting tax collections are likely to be at least $4 billion lower than forecast in the mid-year update.
It would be the fifth consecutive year for revenue to be at such a low level and well short of the 23.7 per cent it inherited from the Howard government.
To make up the shortfall, Mr Swan will say the Government will deliver more cuts as well as changes to the tax system.
"Our focus will be on ensuring the sustainability of priority spending and improving the integrity of the system," Mr Swan will say.
The Government plans to target big multinationals, such as Google and Apple, which use the international tax system to avoid paying tax in rich nations.