"Earlier this year we were talking about how there was going to be a price war, given how wholesale gas prices had come down. There hasn't been one and there was never going to be one," he told the broadsheet.
"There is no rivalry between the suppliers. They control the generation and they each have a comfortable number of customers. They're laughing all the way to the bank ... Not even a company with the power of Tesco could break into this market," he went on.
Centrica, parent company of British Gas, will announce that the provider made a profit of around £500 million over the first half of this year - up dramatically on the £143 million loss it made over the same period of last year.
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