Queen Elizabeth has vowed she will never abdicate.
But it has been suggested that plans are in place for Queen to step aside if she is still on the throne at 95, allowing Prince Charles to assume power.
Palace sources have indicated to the Mail on Sunday that the monarch, who is now 91, may ask for the Regency Act to come into force at that point.
This would see Charles assume the title of Prince Regent and carry out the duties of the monarchy meaning he would be king in all but name.
If the Queen made the decision to enforce the act it would see her effectively retire, much like the Duke of Edinburgh, who at 96, stepped back from royal duties last month.
Royal commentator Robert Jobson said he has been told by high-ranking courtiers that preparations for such a transition are already underway and that a Regency is now a possibility.
Britain has had a regency once before when George IV became Prince Regent in 1811 when his father, George III, suffered episodes of mental illness.
A former senior member of the Royal Household told the MoS: ‘Out of the profound respect the Queen holds for the institution of monarchy and its stewardship, Her Majesty would want to make sure that she has done everything she can for her country and her people before she hands over. She is dutiful to her core.
‘Her Majesty is mindful of her age and wants to make sure when the time comes, the transition of the Crown is seamless.
‘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 reign to Charles.’
Palace staff have apparently been ordered to be ‘up to speed’ on the 1937 Regency Act, which grants power to the heir apparent in the event of illness and ‘for the performance of certain of the Royal functions in the name and on behalf of the Sovereign in certain other events’.
Neither Clarence House or Buckingham Palace have commented on the plans, but there is no suggestion that the Queen is planning to abdicate.
The Queen’s health is said be in remarkable health, but Charles has already filled in on a number of foreign trips during her Diamond Jubilee year including to Australia and New Zealand.
Metro.co.uk has approached Clarence House for comment.