Alistair Carmichael MP, who chairs the Environment, Food and Rural Affairs Committee, said the resignation was “obviously the right thing for him to have done” but added: “I don’t think that South East Water is yet off the watchlist.”

“This is a company that as far as I can see hasn’t started yet the necessary process of turning things around,” he said.

The committee’s highly critical report, published on 1 May, accused the water company of poor leadership, weak governance and a culture where nobody was held accountable.