The first time Donald Trump tried to call Boris Johnson for a chat recently he assumed it was a hoax. He took a call from someone purporting to be the Downing Street switchboard.

“The person had a mild Irish accent and said, ‘This is the No 10 switchboard, we have got the president of the United States for you. I am just going to patch you through to the White House situation room,’” Johnson explained.

“Thinking quickly as I do, I said, ‘To all our listeners on Radio Kilkenny, I was not fooled for an instant.’” Johnson hung up and dialled No 10 “and indeed it was the president”.

This is a standard Boris Johnson anecdote. Slightly surreal and chaotic? Check. Interviewee chuckling as he