HARD-UP families have been hit hardest by energy profiteers who raised household bills despite cutting costs, Labour revealed yesterday.

Average electricity and gas bills have ballooned by £260 since the Tories took power in 2010, according to House of Commons figures.

They show that Britain’s privatised energy scam has seen bills for the poorest 10 per cent of families rise twice as fast as for other households.

The stats were made more shocking yesterday when energy regulator Ofgem revealed that the big six had doubled their profit margins over the past year.

Wholesale gas prices have fallen by 19 per cent since last winter — but profiteers have refused to pass on the savings.

Labour revealed the research before launching a bid today to give Ofgem the powers to cut bills when wholesale prices fall.

“Millions have been ripped off by the big energy firms who never seem to pass on savings to customers,” said shadow energy secretary Caroline Flint.

“These figures show that the poorest households are paying the heaviest price for the Tories’ failure to stand up to the energy companies and

ensure that the full savings from wholesale cost falls are passed on to all consumers.”

German-owned Eon belatedly knocked off 3.5 per cent from its gas bills for its 4.5 million customers in Britain.

But Labour’s figures show that gas bills for the poorest 10 per cent of customers soared by 53 per cent between 2010 and 2013, while electricity costs rocketed by 40 per cent.

That compares to a rise of 7.5 per cent in gas and 23.9 per in electricity for the richest households.

Ms Flint said that Ofgem should cut prices now and pledged that Labour would implement a prize freeze until 2017 if it won this May’s general election.

But Fuel Poverty Action Group said Labour should tackle climate change and corporate power by insulating homes and “listening to the two-thirds of people who want to see a return to publicly owned energy.”

“The proposals do not fundamentally alter our corporate-controlled energy system which leaves thousands of people to die every winter whilst our climate gets wrecked,” said spokeswoman Clare Welton.