Australia's Treasury says there is a hole of more than $10 billion in the costings of the election promises made by the opposition Coalition.
The ABC reports that three independent MPs have received Treasury briefings on the impacts of the election promises made by both the Coalition and the governing Labor Party.
A key independent MP says Opposition leader Tony Abbott needs to explain why Treasury analysis has identified the "black hole" in the Coalition's costings.
Before the election the Coalition said its promises would add about $11.5 billion to the budget bottom line over the next four years.
But Treasury analysis given to Tony Windsor and his fellow independents Rob Oakeshott and Bob Katter shows the Coalition's promises would only add between $860 million and $4.5 billion to the bottom line.
The Treasury document shows the Coalition has costings problems with its plans for health, education, infrastructure and its paid parental leave scheme.
The difference in figures also comes down to the Coalition making significant spending promises without saying which projects would be slashed to pay for those promises.