The news comes after the Queen cancelled several engagements last month due to ongoing health issues.
Queen Elizabeth II is resting after spraining her back over the weekend. The Queen, who was set to attend a Remembrance Day service in London on Sunday, was forced to miss the annual activities after suffering yet another setback to her health.
In a statement released by Buckingham Palace, the Queen's royal communications team said the monarch was "disappointed" to miss the ceremony, where she was expected to lead the nation in paying tribute to those who died in Britain's wars.
"The Queen, having sprained her back, has decided this morning with great regret that she will not be able to attend today’s Remembrance Sunday Service at the Cenotaph. Her Majesty is disappointed that she will miss the service," the statement read.
A royal source also told ET, "It is obviously incredibly unfortunate timing, and nobody regrets the Queen’s absence more deeply than her Majesty herself. Her Majesty is deeply disappointed [she missed ] the engagement which she regards as one of the most significant engagements of the year. [She] hopes to continue as planned with her schedule of light official duties.”
While the Queen would not be in attendance, the palace did confirm that Prince Charles would lay a wreath of poppies on the queen's behalf, as he has done in previous years. Prince William and Kate Middleton were also to be in attendance, along with other members of the royal family.
Sunday's service was set to be the first public appearance by the Queen since spending the night in the hospital last month.
A Buckingham Palace spokesperson told ET at the time that the Queen was in the hospital for "some preliminary investigations."
According to the spokesperson, Queen Elizabeth returned to Windsor Castle the following day at lunchtime and was said to be in "good spirits."
Prior to her hospital stay, the monarch announced that she would be canceling a planned trip to Northern Ireland on the advice of her doctors.
"The Queen has reluctantly accepted medical advice to rest for the next few days," a spokesman for Buckingham Palace said in a statement last month. "Her Majesty is in good spirits and is disappointed that she will no longer be able to visit Northern Ireland, where she had been due to undertake a series of engagements today and tomorrow."
The Queen gave her "warmest good wishes" to the people of Northern Ireland and expressed a desire to visit in the future.
A source told ET at the time that the decision to rest is not COVID-related, though the Queen's condition is not currently being shared.
"She has had a packed schedule recently," the source said, adding that the Queen was "resting at Windsor Castle" on "doctor's advice."
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