Speaking after the Government said Treasury modelling showed low-income households would get an average of $610 in cash compensation but would only experience price rises of $420, Mr Abbott questioned the purpose of the scheme.

''When the Government starts talking about 120 per cent compensation for some people, it gives rise to the understandable suspicion that the ETS is not about the environment, it's really about a political slush fund.''

Mr Abbott called on the Government to release the modelling behind its claims. A Government spokesman said the analysis was based on October 2008 Treasury modelling and updated to reflect the lower carbon price forecast in November's Mid-Year Economic and Fiscal Outlook.

While it released some detail on the impact on low-income households, the Government has held back on similar information for wealthier households.

But it did reveal that 90 per cent of all households would receive assistance. On average those households would receive about $660 in compensation in 2013. Price rises of 1.1 per cent, totalling $624 a year per household, were forecast by that year.

The Environment Minister, Peter Garrett, called on Mr Abbott to back up his claim that bills for the average household would rise $1100 a year. ''You can't run an Opposition by just making things up,'' he said.

Mr Abbott rejected this, saying his figure was based on reports of the Government's own modelling, but he declined to offer more detail.