Writing in The Daily Telegraph, Ofwat Chairman Jonson Cox, has voiced his concern over water profits and taxation.
He said: "It has also been alleged that some companies use shareholder loans to avoid UK taxation.
"At the same time, hard-pressed customers have seen annual bills rise by 13.5pc since 2010-11, while their incomes have fallen.
"I agree that the dichotomy between profits and the prices charged to customers raises business, regulatory and moral questions."
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Sir Bruce Forsyth, Sir Cliff Richard and the Prime Minister have been among those paying tribute to Cilla Black following news of her death.
TV favourite Cilla Black, who has died aged 72, gave viewers a "lorra, lorra laughs" during her long career.
Some rain in the north. Very warm sunshine in the south