Penny Junor suggested Elizabeth II was entering a new phase of her reign when she would not be seen as much in public.

Ms Junor said: “It’s very sad for the Queen because this is the one event in the year that she really, really likes to be at.

“Remembering the war dead is a very, very important part for her annual calendar.

Penny Junor suggested Elizabeth II was entering a new phase of her reign when she would not be seen as much in public.

“The public will be very sad and anxious to hear of yet another setback but clearly she must follow the advice and get herself well.”

The Queen has been under doctors’ orders to rest for more than three weeks after spending a night in hospital for preliminary tests. Buckingham Palace had said it was her “firm intention” to be at the Cenotaph, and announced on Thursday that she would be at the ceremony.

But on Sunday morning, less two hours before she was due to arrive, the Palace said she had sprained her back and could no longer attend.

Ms Junor said: “It’s not surprising because she is 95 years old.

“We’re so used to seeing her out and about and looking years younger than she is that I think we’ve been lulled into thinking she can go on at this kind of pace forever.

“Clearly she can’t. There comes a time in everybody’s life when they have to admit that they are getting older and can’t do the things that they perhaps want to do.”

Suggesting it appeared to mark a new phase in the Queen’s reign, Ms Junor said: “I think we will see more of her on video and probably less of her in the flesh.”

She added: “They should keep her warm and tucked up at home and not exposing herself to the possibility of infections.”

Members of the royal family and senior politicians led the nation in honouring the country’s war dead on Remembrance Sunday.

The event on Whitehall was given added poignancy by a return to pre-pandemic numbers of participating veterans and military, as well as onlookers.

Queen suffers ‘setback’ amid public anxiety for her health, royal writer says