Britain's Queen Elizabeth will not carry out the opening of parliament on Tuesday as the 96-year-old monarch has had a recurrence of mobility issues, Buckingham Palace said on Monday, the latest event she will not attend because of her health.
Her son and heir Prince Charles, accompanied by his eldest son Prince William, will step in to replace her for the set-piece ceremony in which the monarch sets out the government's agenda, the palace said.
"The queen continues to experience episodic mobility problems, and in consultation with her doctors has reluctantly decided that she will not attend the State Opening of Parliament tomorrow," Buckingham Palace said in a statement.
"At Her Majesty's request, and with the agreement of the relevant authorities, The Prince of Wales will read the queen's speech on Her Majesty's behalf, with The Duke of Cambridge also in attendance."
The queen has been forced to cut back on engagements since being hospitalised for a night last October for an unspecified illness, and then being told by her doctors to rest.
The palace declined to give details of Elizabeth's ailment, but a source said her decision to pull out of the parliament opening was related to the problems she had suffered last year, adding it had only been made on Monday.
Elizabeth, the world's eldest and longest-reigning monarch, has continued to carry out many of her duties virtually. Her first public event since falling ill was in April, when she attended a memorial service to her late husband who died last year.
Earlier this week it was announced she would not attend the traditional summer garden parties at Buckingham Palace, but she has continued to carry out regular engagements virtually and some in person at her Windsor Castle home.
The palace source said she would have her regular audiences with the Privy Council and Prime Minister Boris Johnson this week, virtually and by phone.
The State Opening of Parliament is an event of huge pomp and pageantry which traditionally sees the queen travelling to the assembly in a State Coach, escorted by mounted soldiers in ceremonial uniform, while the Imperial State Crown and other regalia travel ahead in a carriage of their own.
The monarch puts on the Robe of State before leading a procession to the House of Lords upper chamber where she sits on a throne and formally opens a new session of parliament, reading a speech outlining the government's legislative plans.
She has missed the occasion twice during her 70-year reign - in 1959, and 1963, when she was pregnant with sons Andrew and Edward. Prince Charles has attended the opening before, but it is the first time that William, also destined to be a future king, will be officially involved.
Britain will hold four days of celebration in June to mark the queen's Platinum Jubilee. Buckingham Palace said last week she was planning to attend most major events during the celebrations but her presence would not be confirmed until on the day.