The Prime Minister's official spokesman said Ofgem has given "a very strong signal" that energy companies will not "get away with" bad practice after the it fined ScottishPower £8.5 million.
Asked if David Cameron was happy with the level of the fine, he replied:
Those must be, of course, decisions for the regulator but I think it does send a strong signal in response to bad practice that was being looked at here.
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One story dominates Thursday's front pages with some newspapers printing emotive pleas to voters to keep the United Kingdom as one.
After a mild start temperatures should pick up, with the south of England seeing highs of 26C.
In Edinburgh tonight you can hear it and feel it. The buzz, the banter of the day and the thrilling sense something big is coming tomorrow.