Energy companies warned Labour leader Ed Miliband that his surprise pledge to freeze prices would hit the building of new power stations, jobs and the livelihoods of 600,000 people dependent on the industry.

British Gas owner Centrica went as far as to say it would either go bust or leave the UK if Mr Miliband's controversial plan was put into action.

In a statement, the supplier said: "If prices were to be controlled against a background of rising costs it would simply not be economically viable for Centrica, or indeed any other energy supplier, to continue to operate and far less to meet the sizeable investment challenge that the industry is facing."

Centrica this week announced it was abandoning two key gas storage projects in East Yorkshire and the North Sea, blaming the set back on the Government for not subsidising new gas storage facilities.

The sector's umbrella group also hit back at Mr Miliband in a strongly worded response to the speech.

Angela Knight, Chief Executive of Energy UK, said: "Freezing the bill, may be superficially attractive, but it will also freeze the money to build and renew power stations, freeze the jobs and livelihoods of the 600,000 plus people dependent on the energy industry and make the prospect of energy shortages a reality, pushing up the prices for everyone.

"No other industry is facing the investment challenge of the energy sector. Last year alone the energy industry invested £11.6 billion - the equivalent of building the Olympic stadium 20 times over.

"We need to invest £110 billion over the next 10 years to build and renew the power stations, the wires and the pipes everyone in the country needs to keep the lights on, our homes warm and to supply the power for British business to compete, to recover and to grow.

"And as for breaking up the energy companies or banning them both making and selling electricity - that is not the way to bring greater competition into the market or to provide the range of services which domestic and business customers want.

"What it does is send a clear message to overseas investors that the UK is closed for business when just today the World Energy Council said the UK has one of the world's fairest and most secure systems for supplying energy.

"Today's announcement is not the adult debate the industry has long been calling for and that customers deserve."

Paul Massara, chief executive of RWE npower, said: "It's very easy for politicians to come up with simple-sounding solutions to difficult problems. But in reality, there are three main factors that influence prices: fixing inefficient housing stock, the investment required to replace the UK's energy infrastructure, and the cost of the buying energy on the global market.

"If the Labour Party can commit to reducing policy costs on household energy bills, stopping the smart meter roll-out, preventing commodity cost increases and accept that there won't be any investment in new power stations and infrastructure, then we could freeze our prices. But will this make things better for Britain?"

Energy firm SSE said in a statement: "We need to do all we can to keep energy prices affordable. At the moment the actual energy consumers use makes up just half of a dual-fuel energy bill.

"Instead of price freezes, which will lead to unsustainable loss-making retail businesses, the Labour Party should put policy costs into general taxation, taking them off energy bills.

"This would wipe £110 off the average person's bill and shift the cost away from those who can't afford to pay and on to those who can."

But Ramsay Dunning, general manager at Co-operative Energy, cheered Miliband's proposal, saying: "We welcome the pledge Ed Miliband has made, to freeze energy prices if the party is elected in 2015. A tough approach, like this, is required to tackle the spiralling profits the Big Six continue to enjoy and, most importantly, to create a fairer deal for customers who are struggling or in some cases, unable to pay their energy bills."

The European Commission has signalled its opposition to similar price regulation actions in seven or eight EU member states - underlining its preference for free markets.

But at the same time it has taken no action against a recent comparable Belgian policy, suggesting it may show toleration.

Simon Walker, director general of the Institute of Directors, said: "We should think very, very carefully before piling more distortion on an already grossly distorted energy market. Price controls only add greater uncertainty to companies who we need to take the financial risks of energy investment.

"It was also a great shame not to hear anything about the potential benefits of domestic shale gas exploration, which must feature as part of the UK's long-term energy strategy."