London(CNN) Britain's Queen Elizabeth II has been told by doctors to rest for at least the next two weeks and not undertake any official visits, Buckingham Palace said in a statement Friday.
The announcement comes more than a week after the monarch, 95, spent a night in the hospital for what a spokesman described at the time as "preliminary investigations."
"Her Majesty's doctors have advised that she should continue to rest for at least the next two weeks. The doctors have advised that Her Majesty can continue to undertake light, desk-based duties during this time, including some virtual audiences, but not to undertake any official visits," the palace said in its statement Friday.
"Her Majesty regrets that this means she will be unable to attend the Festival of Remembrance on Saturday, 13th November. However, it remains The Queen's firm intention to be present for the National Service of Remembrance on Remembrance Sunday, on 14th November."
The palace announced Tuesday the Queen would not be making a planned appearance at an evening reception for world leaders she was going to host at the COP26 summit next week, and would instead make a video address.
As the head of state, representing her country is a key part of the Queen's constitutional role. Having to cancel her in-person appearance at the largest gathering of world leaders to ever take place on British soil would have been disappointing to the Queen.
The Queen recorded a COP26 speech Friday afternoon which will be shown at the conference on Monday, according to the royal source.
A royal source told CNN the Queen "remains in good spirits" and continues "light duties." The advice was a "sensible precaution" from medics and the monarch's diary was light for next week, the source said Friday.
The Queen had canceled a trip to Northern Ireland last week following medical advice to rest more, but resumed "light duties" on Tuesday, including two virtual audiences with the South Korean and Swiss ambassadors to the UK.
A source close to the palace told CNN at the time her overnight stay in the hospital last week was "not Covid-related." She returned to Windsor Castle "in good spirits" after one night, the palace said.
The palace has not disclosed any details about the Queen's health, but has consistently stressed the monarch was in good spirits and able to undertake some duties.
On Thursday, the palace released a snippet from a video call earlier in the day. In the clip, she joked with the 2020 winner of the Queen's Gold Medal for Poetry, David Constantine, who was presented with his medal at Buckingham Palace. "I don't know what you do with it... You put it in a cupboard?" she quipped.
Earlier this month, the Queen made the decision to use a walking stick in public for the first time "for comfort."
While the Queen does not appear to be slowing down when it comes to her ceremonial responsibilities, she has since handed off long-haul tours to other family members.
Still, she is traveling extensively across the UK, with CNN's conservative estimates showing the Queen traveled more than 1,000 kilometers (621 miles) from October 1 through October 19.
Last week, she declined an honor of being named "Oldie of the Year" by a British magazine, saying she did not meet "the relevant criteria." She "politely but firmly" declined the award through her assistant private secretary with "warmest best wishes."