Kevin Rudd is sticking to his claim of a $100 billion blow-out in private health insurance rebates, despite the figure not being included in the latest intergenerational report.

"It's a basic statistical fact," the prime minister told ABC Radio on Tuesday.

Mr Rudd on Sunday said the figure was contained in the report, released by Treasurer Wayne Swan on Monday.

While the report showed the lack of a means test for the 30 per cent rebate would cost $1.9 billion over three years, there was no reference to the $100 billion figure over the "several decades" quoted by Mr Rudd.

"All the underpinning data provided by the Treasury in the preparation of that report contains that number," he said.

"The bottom line is that this is the cost to Australia of the Liberals continuing to block much-needed reform to private health insurance for the wealthiest Australians."

The opposition has dismissed the projection, describing it as "exaggerated rhetoric".

The government will make a second attempt on Wednesday to have parliament approve a means test for the rebate.

Liberal senator Guy Barnett said Mr Rudd's claim showed he was getting "a little bit desperate".

"He's not quite sure how to respond to (Opposition Leader) Tony Abbott," he told reporters.