A report by the government-appointed taskforce, headed by British Airways chairman Lord Marshall, said the tax could "probably play a role if businesses of all sizes and from all sectors are to contribute to improved energy efficiency and help meet the UK's emissions targets."

Business leaders balk

Lord Marshall's report has worried business leaders

The business-related proposals from Lord Marshall, a former chairman of the Confederation of British Industry, sparked swift criticism from the the CBI's incumbent Director General Adair Turner.

Mr Turner expressed doubts about the effectiveness of an energy tax.

"We would certainly caution against any new taxes on business...in the current uncertain economic climate," he said.

Legal obligations

The report coincides with a high-profile UN meeting in Argentina to discuss climate change.

The talks will set targets and permits for countries to meet their greenhouse gas targets.

The UK is legally obliged to reduce its greenhouse gas emissions by 12.5% between 2008 and 2012, after signing up to the climate accord, drawn up in Kyoto, Japan, last year.

Tradeable emissions

Another option suggested by the report was a system of tradeable emissions permits allowing countries and companies to respect emission levels collectively through trade.

The disadvantages of the permits mean the system would take much longer to implement than a new tax and would be unlikely to involve small and medium sized companies which account for 60% of UK company air pollution.

Lord Marshall said the government should consider a pilot emissions scheme to allow industry to learn how to take part in any international scheme.

His report tried to reassure the business community that any tax would be designed in a way which would protect the competitiveness of British industry.

It recommended that any tax changes should be made in a gradual way to help business planning.