The book, set for release on 10 October and currently being serialised by the Daily Mail – where Johnson is a columnist – reflects on the Queen’s final days at Balmoral, Scotland. Johnson resigned from office just two days before the Queen’s death in September 2022, amidst ongoing speculation about the precise cause of her passing.

"I had known for over a year that she had a form of bone cancer, and her doctors feared she could decline rapidly at any moment," Johnson wrote in the memoir. This revelation marks the first time a senior government figure has publicly commented on what might have contributed to the Queen's death, which was officially attributed to “old age” on her death certificate.

Johnson is not the first former prime minister to share personal reflections on the Queen in an autobiography. However, while leaders such as Tony Blair, Gordon Brown, and David Cameron have touched on their time with the monarch, Johnson’s account stands out for its level of detail.

As is customary, Buckingham Palace has chosen not to comment on books about the Royal Family and has neither confirmed nor denied Johnson’s claims.

Johnson, who served as Prime Minister from 2019 to 2022, recounts his final audience with the Queen at Balmoral, where he submitted his resignation. Upon arrival, he was met by the Queen’s private secretary, Edward Young, who informed him of her significant decline over the summer. Johnson reflects that during their last meeting in the Queen’s drawing room, it was clear her health had worsened.

"She seemed paler and more stooped, with dark bruises on her hands and wrists, likely from drips or injections," Johnson wrote. "But her mind, as Edward had assured me, remained sharp, and she still occasionally flashed that radiant white smile, which lifted the mood instantly."

Johnson described the privilege of his weekly audiences with the Queen as "a balm" and spoke of her enduring influence. "She exuded a sense of service, patience, and leadership that made you feel you would, if necessary, give your life for her," he remarked. "It may sound extreme to some, but that loyalty remains central to our system. We need someone kind, wise, and above politics to embody the best of our nation, and she did so with remarkable brilliance."

The Queen, known for her discretion, never publicly shared details of her health. Royal household aides continue to assert that members of the Royal Family are entitled to the same medical privacy as any other individual.

While King Charles III and Catherine, the Princess of Wales, have been more forthcoming about their personal health challenges, both have refrained from revealing specific details of their cancer diagnoses. Aides have explained that they chose to share their experiences to raise awareness, rather than focus on the particulars of their illnesses.