Australian Prime Minister Julia Gillard has revealed a $A12 billion hole in the country's finances.
In 2012, the federal government insisted it would deliver a $A1.1 billion budget surplus, but in December dumped this promise and has been revising down revenue estimates since.
On Monday, Ms Gillard will announce that revenue is now expected to be $12 billion lower this financial year than forecast in October 2012, the ABC reports.
However, Ms Gillard is promising the government will still use the May budget to push on with a school funding plan and the National Disability Insurance Scheme.
She described these as investments for a stronger and smarter nation and said it would be a failure not to proceed with them.
Ms Gillard said the revenue shortfall creates a "significant fiscal gap over the budget period", setting the scene for deficits in future years.
Finance Minister Penny Wong blamed "unforeseen circumstances" and said the Treasury didn't anticpate this.
However, Opposition leader Tony Abbott said the government is simply spending more than it earns.
