Centrica chief executive Sam Laidlaw told ITV News Business Editor Laura Kuenssberg that British Gas profits rose because of increased consumption and that margin per household actually fell.
He said that wholesale gas costs rose "by about 13%" and not all of that increase was passed on to customers, "which is why our margins actually went down year-on-year."
"We had a cold winter - much colder than the previous winter, which was actually unusually warm - so we sold a bit more gas, which is why the British Gas profits were up," he added.
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