Before his term as European Commission president, in the decade running to 2014, Mr Barroso was the Portuguese prime minister. He told the Financial Times: “Of course I know… the EU, I also know relatively well the UK environment… If my advice can be helpful in this circumstance I’m ready to contribute, of course.”

Mr Barroso replaces Mr Sutherland as Goldman’s chairman of its international business. The Irishman stepped down last summer after more than two decades with the bank. Mr Sutherland said that his successor’s “advice and counsel in this time of monumental change and uncertainty… will be very important”.

Mr Sutherland now works as a special representative of the secretary-general of the United Nations for Migration and Development. He said yesterday that “the insanity of Brexit and its flawed anti-immigrant narrative is now plain to see, and not just all over the EU but increasingly in the UK”.