Energy suppliers are not worried about providing a competitive market for customers, according to the UK's watchdog.
The director of campaigns of energywatch, Adam Scorer, made the comment after ScottishPower recently announced plans to follow in the footsteps of British Gas, EDF Energy and npower by upping its domestic tariffs.
He stated that the "near-identical" price increases may not have done very much to persuade consumers that the suppliers are working in their best interests, before calling for action on the issue.
Mr Scorer also urged the Competition Commission to investigate the price hikes, saying such a move is now "a matter of urgency".
Last week, new research by the watchdog suggested that energy suppliers also need to improve the complaints service they offer to consumers.
Around 97 per cent of who have complained about the service they have received claim their energy provider failed to deliver on what they promised to consumers.
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