The Prince of Wales will miss one of King Charles's major milestones this autumn, and it's for a very good reason.
Charles, 74, will deliver his first King's Speech at the state opening of Parliament on 7 November.
Commons Leader Penny Mordaunt confirmed the date in a statement to MPs, with Parliament set to be prorogued – temporarily shut – in the days leading up to the ceremony.
The speech offers Prime Minister Rishi Sunak the chance to set out his priorities ahead of a general election expected next year.
Charles has previously deputised for the late Queen to open parliamentary sessions but this will be his first King's Speech as monarch.
Prince William was given permission to open Parliament with his father in their capacities as "counsellors of state" last year, as the late Queen Elizabeth II was suffering with mobility problems. See the moment here...
Two of these counsellors have to be present to carry out this duty on behalf of the head of state.
But on 7 November, William will be in Singapore for the third Earthshot Prize Awards, which focuses on finding solutions to big environmental challenges.
SEE: Prince William's eco-friendly addition to Windsor home
In a statement, Ms Mordaunt said: "I can confirm that the state opening of Parliament will take place on 7 November 2023. As is usual, the current session of Parliament will be prorogued ahead of the King's Speech and this time will be used to enable logistical and security preparations for the state opening of Parliament. The likely date of prorogation will be confirmed in due course."
It is not known at this stage whether the state opening will feature all of the major ceremonial regalia, including the wearing of robes.
In recent years, the royals have worn smart morning dress for the ceremony.
Who are the King's Counsellors of State?
In the event that His Majesty cannot undertake his official duties as Sovereign on a temporary basis due to illness or absence abroad, two or more Counsellors of State are appointed by Letters Patent to act in His Majesty's place.
By law, Counsellors of State include the Sovereign's spouse and the next four people in the line of succession who are over the age of 21.
As listed on the royal family's website, the King's Counsellors of State are Queen Camilla, the Prince of Wales, the Duke of Sussex, the Duke of York and Princess Beatrice.
Prince Harry now resides in the US after stepping back from royal duties in 2020.
Prince Andrew no longer carries out a public role, after stepping down in November 2019, following his controversial TV interview with BBC Newsnight, which focused on his connections to convicted sex offender Jeffrey Epstein.
Meanwhile, Andrew's eldest daughter, Princess Beatrice, has a full-time role as Vice President of Partnerships and Strategy at tech company Afiniti.