The Australian government has unveiled plans to impose a tax on carbon emissions¹ for the worst polluters.

澳大利亚政府公布几项计划，将要对二氧化碳排放最严重的企业征税。

Prime Minister Julia Gillard said carbon dioxide emissions would be taxed at A$23 ($25; £15) per tonne from 2012.

The scheme - the country's biggest economic reform in a generation - will cover some 500 companies that are responsible for most of the pollution.

Households are expected to see consumer prices rise by nearly 1%, and the move has been criticised by the opposition².

Critics argue the levy³（征税） would damage economic competitiveness.

Australia is one of the world's worst emitters of greenhouse gases per head of population.

The country relies on coal for 80% of its electricity generation, and is a major coal exporter.

Charm offensive

The government plans to include in the new scheme any company that produces at least 25,000 tonnes of carbon dioxide per year.

However, agriculture, forestry⁴ and land will be excluded（排除） from the levy. Motorists are also to be exempt⁵, except for heavy lorries.

Steelmakers, coal mines and electricity generators⁶ will receive compensation to ensure they stay in business. Other tax cuts are planned for consumers.

"As a nation, we need to put a price on carbon and create a clean energy future," Ms Gillard told a news conference in Canberra.

"Australians want to do the right thing by the environment."

The prime minister is due to make a televised address later on Sunday to try to sell the package to the nation.

The energy industry and the political opposition have mounted a vociferous⁷（喧嚷的） campaign against the carbon tax, with protests in all of Australia's major cities in March.

Critics argue a levy would damage economic competitiveness.

Opinion polls show roughly 60% of voters against the policy.

The government hopes to win them over by spending some of the cash raised by the carbon tax to compensate⁸ households for higher energy bills.

It is promising⁹ tax cuts for low and middle-income households, as well as increased state pension and welfare payments.

However, Australia's ABC national broadcaster says households are expected to see consumer prices - including food - rise by an average of 0.7% due to the effect of the carbon prices on large emitters.