Charles III was formally proclaimed as king by the Accession Council Saturday during a historic ceremony at St. James Palace.
"I shall strive to follow the inspiring example I have been set in upholding constitutional government and to seek the peace, harmony and prosperity of the peoples of these islands, and of the Commonwealth realms and territories throughout the world," the King said.
The ceremony was attended by Prince William of Wales and the Kings wife, Camilla who has become Queen Consort.
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Garter Principle King of Arms, David Vines White, then read the proclamation of King Charles III from the Friary Court balcony of St James's Palace.
Charles automatically became King upon the death of his mother, but the Accession Council confirmed his role with the attendance of the Privy Councilors.
The United Kingdom’s newest monarch paid tribute to his recently deceased mother, Queen Elizabeth II.
"My mother gave an example of lifelong love and of selfless service," he said. "My mother's reign was unequalled in its duration, its dedication and its devotion."
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The king approved an order that declared the day of his mother’s funeral a federal holiday.
The Associated Press and Landon Mion contributed to this report.
