Industry watchdog Consumer Focus has called for Britain's major energy suppliers to be investigated to make sure they are giving their customers good value for money.
The official watchdog, which is tasked with representing gas and electricity customers, raised its concerns after five of the "Big Six" energy suppliers reduced their prices by between four and eight per cent within days of each other, reports the Telegraph.
Robert Hammond, gas expert at Consumer Focus, told the publication that energy suppliers are acting like an "oligopoly". Their similar price reductions are also making it more difficult for consumers to compare energy providers.
"How can there be serious competition when they all change their prices at nearly identical times and by about the same amount," he commented.
Consumer Focus called for the matter to be referred to the Competition Commission, so it can be determined whether or not energy suppliers are operating fairly.
Earlier this year, industry regulator Ofgem raised concerns about the way energy providers are treating customers when it emerged that each company was making an average annual profit equal to £105 per customer.
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