It is not only Barclays shareholders who are angry with Jes Staley. Some of his fellow bankers at rival institutions are furious at the Barclays chief executive for attempting to unmask a whistleblower.

They believe his actions will undermine efforts to encourage potential whistleblowers, not only at Barclays but also at their own banks. “This is exactly what we don’t need,” says a senior executive at another investment bank.