Speaking the morning after Treasurer Wayne Swan delivered a $58 billion deficit budget, Mr Rudd said the government must ensure that its policies to boost the economy can be backed up with bi-partisan support.

"These decisions are really, really tough,'' Mr Rudd told Fairfax Radio Network on Wednesday.

"We believe we have a mandate from the Australian people to serve out our full term but it is really important, absolutely important, that this budget is passed in its entirety.

"We must ensure that our actions to support the economy now and jobs and infrastructure investment, and our pensions and payments on parental leave are supported by the $22 billion in savings.

"That's why it is important, because of the Senate, for us to know whether we have full support, and what on earth is their confused position on temporary borrowing and temporary deficit.''

Mr Rudd avoided saying he had broken pre-election promises with the changes in superannuation, saying instead the government had not been able ``to fulfil policy commitments''.

"We've had the biggest single hit in our national income and in tax revenue to the Australian government since the Great Depression,'' Mr Rudd said.

"It's created some fundamental thinking, not just in our government, but in all governments around the world, and we've had to make tough decisions.''

He defended the government's changes to superannuation saying it would mainly affect those in upper pay ranges - people earning an average of $221,000 per year or 1.8 per cent of the population.

He said the overwhelming benefits of the arrangement brought in by the Howard government assisted those at the very top of the income range.

He said the government had to provide sustainable reforms for everybody in order to pay for such things as pension increases.