Prince Charles released a deeply personal statement following the death of his mother, the Queen, on Thursday.
It read: "The death of my beloved Mother, Her Majesty The Queen, is a moment of the greatest sadness for me and all members of my family.
"We mourn profoundly the passing of a cherished Sovereign and a much-loved Mother. I know her loss will be deeply felt throughout the country, the Realms and the Commonwealth, and by countless people around the world.
"During this period of mourning and change, my family and I will be comforted and sustained by our knowledge of the respect and deep affection in which The Queen was so widely held."
The poignant statement was notably left unsigned by the new King, 73, as a mark of respect for his mother, who reigned for 70 years.
READ: Prince Charles's new title confirmed following death of his mother, the Queen
WATCH: The Queen's 70-year reign in pictures
Charles' new title was confirmed by the new Prime Minister, Liz Truss.
Speaking outside Downing Street as she paid tribute to the Queen, she said: "Today the Crown passes, as it has done for more than a thousand years, to our new monarch, our new head of state, his majesty King Charles III."
Clarence House has also confirmed The Prince of Wales's new title.
MORE: Why Princes Charles is heading back to Buckingham Palace so soon
Prince Charles pictured with the Queen at the Jubilee celebrations in June
The news of the Queen's death was announced shortly after 6pm on Thursday 8 September. The official message read: "The Queen died peacefully at Balmoral this afternoon. The King and The Queen Consort will remain at Balmoral this evening and will return to London tomorrow."
The new monarch had dashed to the Queen's bedside.
MORE: The Queen's obituary: Her Majesty's extraordinary life of service
Charles was joined by the monarch's other children, the Princess Royal, the Duke of York and the Earl of Wessex, and the Duke of Cambridge, now heir to the throne, with the Duke of Sussex also travelling there.
The royal family and their households traditionally enter into Court Mourning following the death of a sovereign.
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