The Queen is to miss the royal garden party season in her platinum jubilee year and will be represented by other members of the royal family, Buckingham Palace has said.
A spokesperson said details on attendance would be confirmed in due course.
The 96-year-old monarch, who has been experiencing mobility issues in recent months, will not be at the events that are taking place for the first time since 2019.
It is understood the reason is the traditional format of the garden parties, in terms of the length of time they last and the time she would usually spend standing and walking to greet the lines of invited guests.
There are three garden parties in Buckingham Palace garden each summer, as well as another at the Palace of Holyroodhouse in Edinburgh.
It was announced on Thursday that the parties would return this summer after being cancelled for the last two years due to the Covid pandemic.
The three events at Buckingham Palace will take place on the next three Wednesdays of this month – 11, 18 and 25 May. The Holyroodhouse party will be on 29 June.
The parties are held for guests in recognition of their positive contributions to communities across Britain.
This year there will also be a Not Forgotten Association annual garden partyon 12 May, hosted by Princess Anne, who is patron of the charity.
The association provides entertainment, leisure and recreation for wounded, injured or sick men and women serving with the military, and veterans with disabilities.