The ceremony at St. James’ Palace, which formally confirms the king’s succession from his mother, will be televised for the first time in history.
The Accession Council, a group of royal advisers, Lords, City of London officials and Commonwealth diplomats, will also formally announce the reigning name of the new monarch: King Charles III.
The Prime Minister accompanied Prince William, Camilla the Queen Consort, Archbishop of Canterbury Justin Welby and Lord President Penny Mordaunt to the throne room where Mrs Mordaunt began presiding over the event.
The group formed the “platform party” who took turns signing the proclamation document before it was read out later in the morning.
Mrs. Mordaunt then issued eight orders traditionally ensuring the announcement of a monarch’s proclamation to their subjects, including salutes and publication of the document in the publications of London, Edinburgh and Belfast.
The ceremony followed as Charles stepped forward to make his statement.
He said: ‘My lords, ladies and gentlemen, it is my most solemn duty to announce the death of my beloved mother the Queen.
“I know how deeply you, the entire nation, and I think I can say that the whole world sympathizes with me in the irreparable loss we have all suffered.
“It is the greatest comfort to me to know the condolences so many have extended to my sister and brothers and that such overwhelming affection and support should be shown to our entire family at our loss.
“To all of us as a family, regarding this kingdom and the wider family of nations it is a part of, my mother set an example of lifelong love and selfless service.
‘My mother’s reign was unparalleled in duration, dedication and devotion. Even as we mourn, we give thanks for this very faithful life.
“I am very much aware of this great legacy and of the duties and heavy responsibilities of sovereignty which have now passed to me.
“In assuming these responsibilities, I will strive to follow the inspiring example I have been given in maintaining constitutional government and will strive for the peace, harmony and prosperity of the peoples of these islands and of the realms and territories of the Commonwealth around the world.
In this purpose I know that I must be sustained by the affection and loyalty of the peoples to whose sovereign I have been called, and that in the discharge of these duties I shall be guided by the council of their elected parliaments.
In all this I am deeply encouraged by the constant support of my beloved wife. I take this opportunity to affirm my willingness and intent to continue the tradition of relinquishing the hereditary income, including the Crown Estate, to my Government for the benefit of all, in exchange for the Sovereign Grant, which my official duties as head of state and head of the nation.
“And in carrying out the task that has been laid upon me and to which I now dedicate what remains of my life, I pray for the guidance and help of Almighty God.”
Charles then read an oath to maintain the security of the Church of Scotland, which was produced as a document that he had to sign along with Camilla and William.
For the first time, Charles signed an official royal document ‘R’ for Rex – Latin for King – while William signed ‘P’ for Princips, the Latin for Prince.
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