Energy regulator Ofgem has proposed that the Big Six energy firms should be investigated by the Competition and Markets Authority.
In an open letter to Britain's main energy suppliers, the regulator's chief executive officer Dermot Nolan said they were concerned that companies were "not passing on savings to customers".
He said: "A concern that savings were not being passed on to customers was one of the reasons why we have proposed a referral of the energy market to the Competition and Markets Authority for investigation."
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Around 40 events will be staged across the UK today as nurses step up their campaign for the Government to end the cap on public sector pay.
Within the next seven days, we are going to witness some of the most significant change in the British Monarchy for many years.
Prince William is set to complete his final air ambulance pilot shift before taking taking up royal duties full-time.