Boris Johnson hailed the late Queen Elizabeth as the “most impressive” person he has ever met and said she made his three years as Prime Minister “bearable” in a new interview.

The former Tory leader said the late monarch, who died two days after he resigned as PM, was like a grandmother he could confide in as he praised her incredible knowledge and wisdom.

Speaking on today’s (Fri) Rosebud with Gyles Brandreth podcast, Mr Johnson said she remained in “wonderful, sparking” form during their last meeting despite reportedly suffering from a form of bone marrow cancer.

Mr Brandreth, a close friend of the late Queen and her husband Prince Philip, revealed he had heard the 96-year-old had a form of myeloma in his biography, Elizabeth: An Intimate Portrait, published three months after her death.

He wrote the diagnosis “would explain her tiredness and weight loss and those ‘mobility issues’ we were often told about during the last year or so of her life”.

Mr Johnson also detailed the diagnosis in his memoir, Unleashed, saying: “I had known for a year or more that she had a form of bone cancer, and her doctors were worried that at any time she could enter a sharp decline.”

But Buckingham Palace has never confirmed the report and her death certificate simply stated “old age”.

After naming the late Queen the most impressive person he’s encountered, Mr Johnson said: “Her late Majesty the Queen was the most phenomenal fund of wisdom and knowledge…. very wise.”

He added: “I always felt buoyed and bucked in her presence. You could not help feeling the cares lift when you went into her room.

“And it all seemed much easier and more bearable. Because she’d seen it all before. And there was nothing you could tell her that would shock her.

“I mean she was like having tea with your favourite grandmother and telling her things that you wouldn’t dream of telling your parents.”

The politician said even though there were signs the Queen was ill when they last met at Balmoral, she was still as sharp as a button.

He told Mr Brandreth that he was “slightly dreading” their final meeting, where he tendered his resignation as Prime Minister shortly before the monarch invited Liz Truss to form a Government.

“I arrived in good time as you do, and we were kept waiting for quite a while by the courtiers and by Edward Young, her wonderful private secretary,” Mr Johnson recalled.

“And Edward said to me ‘I’m afraid she’s gone down quite a lot over the summer’, and so I was sort of bracing myself.

“But actually she was on sparkling form. Yes, you could tell that she was tired, and you could see that she’d been having treatment of some kind because of the bruising on her wrist from injections and so on, but she was absolutely on it. She followed everything.”

He added: “Two days later I’m sad to say she died, but she was totally, totally on it and charming, and thoughtful, thoughtful about you. That was I think a large part of her charm. She was able to put herself in your shoes.”

Asked what the lesson is from his life that he’d like to share with people, he said: “Well, I think it’s Her Maj. I think that her advice about avoiding bitterness is very good.”

Mr Johnson also spoke about his annoyance that people like himself heed magpie superstitions – the Queen included – when other countries do not hold them.

He said: “It really annoys me, when I go to Australia, or America, or Canada, France, they don’t care about magpies, they don’t worry about magpies at all.

“I freak out, I have a real problem. But she, her Majesty the Queen, or so she claimed – maybe she was just indulging me – but she said she had exactly the same thing.”

He said to stave off bad luck, if she saw a solitary magpie, the Queen would greet it with “Good morning Mr Magpie” and say the day’s date – advice he has followed.

He said: “I find that very useful, I have to say – news you can use.”

But while Mr Johnson spoke fondly of the late Queen, a new book claimed that the 96-year-old monarch thought he was an “idiot”.

Political journalist Tim Shipman writes in his book Out that the late Queen thought he was “better suited to the stage” than politics; and when he resigned two days before her death she told a senior courtier in jest: “At least that idiot won’t be organising my funeral.”

The full interview can be heard today on the Rosebud with Gyles Brandreth podcast on all major platforms.