Queen Elizabeth II’s final moments were described as “very peaceful” in a memo written by her private secretary, which also revealed she “wouldn’t have been aware of anything”.

A note about the late Queen’s death at Balmoral on September 8 2022 was written by Sir Edward Young in a memo which has been reported by the Daily Mail.

He noted: “Very peaceful. In her sleep. Slipped away. Old age. She wouldn’t have been aware of anything. No pain.”

The document, which is now in the Royal Archives, forms part of a new biography of the King – Charles III: New King, New Court. The Inside Story – by the Mail’s royal writer Robert Hardman, which is being serialised by the paper.

The book also reveals how, shortly after Sir Edward wrote his note, a footman brought a locked red box of paperwork found at the late Queen’s deathbed which contained two sealed letters – one to her son and heir and the other to Sir Edward himself, the Mail reports.

The box also contained her choice of candidates for the Order of Merit for “exceptionally meritorious service” across the Commonwealth.

The book reveals the late Queen’s death was so sudden that Charles had to rush to Balmoral by helicopter and read his “London Bridge” (the plans for events following the Queen’s death) notes on the way.

It adds that the King and Queen Camilla spent an hour with the late Queen privately before she died.

And Princes Anne and the late Queen’s senior dresser, Angela Kelly, alternated at her bedside, along with Rev Kenneth MacKenzie, a minister at nearby Crathie Kirk.

Charles called both of his sons and told them to travel up to Scotland as soon as possible to say their goodbyes, the biography adds.

Charles, who had gone out to gather mushrooms and clear his head after seeing his mother, received the news that she had died as he was driving back to Balmoral when his most senior aide took a call, the Mail reports. Charles pulled over and was addressed for the first time as “Your Majesty”.

Then, when Charles called William via the palace switchboard to break the news, he told the operator “it’s me” as he realised he could not reveal that he was king yet.

The King did try to contact his younger son to tell him personally, but Harry was already in the air and he could not get through, the book reveals.