Boris Johnson has revealed that the late Queen Elizabeth joked: "Were you naked?" when he informed her about his nightmare of being late to see her and Prince Philip.
The former UK Prime Minister reflected on his conversations with the late monarch as the first anniversary of her death approaches and recalled an example of her quick wit.
Writing in his Daily Mail newspaper column, Boris said: "I once told her that I had a nightmare that I had been late for her and the Duke (of Edinburgh).
"'Oh yes', she beamed, and I could tell that she had heard this one before, probably from other PMs. 'Were you naked?' she asked, because it turns out that is a common feature of such dreams."
Boris, 59, described his meetings with the Queen as a blend of the "tutorial and confessional" and understood how she charmed politicians ranging from Winston Churchill to Barack Obama.
He wrote: "When you were with her, you could see why the elderly Churchill had such a crush on her. You understood why Barack Obama was so entranced that he stayed up drinking with her so late, they say, that the footmen had to come and cough to indicate that the evening was at an end.
"You felt even though she had seen it all, knew it all, she also enjoyed and appreciated politics in all its intricacy and absurdity."
Boris also disclosed how the late monarch let him exercise in the Buckingham Palace gardens when he was ill and informed him that one of the UK's F-35 fighter jets had blown a gasket and fallen into the Mediterranean sea.
He reflected: "If she was surprised by my ignorance, she didn’t let it show. She was never less than supportive, and always encouraging, always thinking about how others might be feeling."