Britain's under-fire energy suppliers said today they will cut household bills after the Government confirmed a shake-up of green levies.

British Gas said it will reduce gas and electricity prices by an average of 3.2%, equivalent to £41 from an annual dual fuel bill, with an extra £12 rebate for the Government's Warm Home Discount scheme.

Rival Scottish & Southern Energy said it expects a saving for the typical dual-fuel customer of around 4% before the end of March, equivalent to a saving of around £50 for a typical dual-fuel customer.

The moves come after C hancellor George Osborne confirmed that the costs of some energy-efficiency schemes will be rolled back in this week's Autumn Statement.

Npower said it does not plan to increase energy prices before spring 2015, unless there are increases in wholesale energy costs or network charges.

The cut in British Gas bills comes two weeks after it hiked electricity bills by 10.4% and gas tariffs by 8.4%, adding around £123 to the average annual bill.

British Gas managing director Chris Weston said today: "British Gas is pleased to be cutting energy bills by an average of £53 from January 1.

"We've been able to do this because the Government has committed to making changes to the environmental and social obligations that are paid for through energy bills. These changes will now allow us to help more people at a lower cost."

The Government is cutting the cost of the energy company obligation (ECO), an insulation scheme delivered by major energy suppliers, in a move that should shave £30-£35 off bills, on average, next year.

The Department of Energy and Climate Change also announced it is establishing a rebate, saving the average customer £12 on their bill for the next two years.

Electricity companies will also take voluntary action to reduce network costs in 2014/15, funding a one-off reduction of around £5 on electricity bills.

Energy and Climate Change Secretary Ed Davey said: "Energy bills are a big concern for many people, which is why we've been working to reform the energy market, increase competition and make it easier for people to shop around and switch supplier.

"Today's announcement confirms a serious, workable package which would save households around £50 on average."

The Government said it will introduce measures that will boost energy efficiency, worth £540 million over three years.

These include offering buyers of new homes up to £1,000 to spend on energy-saving measures - equivalent to half the stamp duty on the average house - or up to £4,000 for particularly expensive measures.

The G overnment will also introduce a scheme to support private landlords in improving the energy-efficiency of their properties, which will improve around 15,000 of the least energy-efficient rental properties each year for three years.

A further £90 million will be spent over three years improving the energy efficiency of schools, hospitals and other public sector buildings.