While still a Princess, Elizabeth poignantly said in a 1947 speech: “I declare before you that my whole life, whether it be long or short shall be devoted to your service.”
But a new book by Royal correspondent Robert Jobson, who toured with Prince Charles for a year, suggested Her Majesty will stand aside to allow Charles to become Prince Regent in just three years’ time.
Mr Jobson said in the past: “I understand the Queen has given the matter considerable thought and believes that, if she is still alive at 95, she will seriously consider passing the reins to Charles.
“Her Majesty is mindful of her age and wants to make sure when the time comes, the transition of the Crown is seamless.”
If Prince Charles becomes Prince Regent, it means he will be able to rule the monarchy, without formally becoming King.
The Regency Act 1937 made way for a regent to step in should a monarch become incapacitated.
The act states: “In the event of incapacity of the sovereign through illness, and for the performance of certain Royal functions in the name and on behalf of the sovereign in certain other events.”
The Queen will hand over the reins to Prince Charles sooner than expected
The Queen has held the throne since the tender age of 25
The act says this only lasts until the monarch is able to resume duties, so the Queen would have to make an exception for Charles as Prince Regent.
Last April, Charles was appointed as the Queen’s successor as Head of the Commonwealth, despite being considered less popular than his son William.
Delivering a speech at Buckingham Palace to the leaders of the Commonwealth, Her Majesty the Queen said: “It is my sincere wish that the Commonwealth will continue to offer stability and continuity to future generations, and will decide that one day the Prince of Wales should carry on the important work started by my father in 1949.”
The appointment came despite concerns within the Commonwealth that Prince Charles would not make a suitable head, with a growing campaign to elect a leader on a rotational basis.
The Regency Act 1937 made way for a regent to step in should a monarch become incapacitated
Last April, Charles was appointed as the Queen’s successor as Head of the Commonwealth
There have already been calls for the role of King to surpass Prince Charles and pass straight to his son, reinforcing the popularity of the Duke and Duchess of Cambridge.
A poll by Prospect Magazine last year showed that a fifth of people would be less supportive of the monarchy if Charles was King.