David Cameron insists that he was right to hold the Brexit referendum while claiming he is “truly sorry” at the uncertainty and division it has brought and admitting: “I failed.”

The former prime minister says that Leave’s victory more than three years ago has left him “hugely depressed”. He worries “desperately” about the consequences and admits that some will never forgive him.

But Mr Cameron, 52, argues that a changing European Union meant that an “inevitable” referendum was already overdue by the time voters went to the polls on June 23, 2016, and that it was the “right approach”.