Caroline Flint MP, Labour’s Shadow Secretary of State for Energy and Climate Change, responding to the release of the CMA’s provisional findings, said:

“This report from the CMA makes clear that the energy market is broken and ordinary families are paying the price. The Big Six have been overcharging households by more than a billion pounds every year.

"Wholesale costs are now at a five-year low but this is still not being reflected in household bills. Rather than writing a letter to the Big Six begging them to cut prices David Cameron needs to take proper action to protect consumers by improving transparency and competition, and by giving the regulator the power to cut prices.”