King Charles III addressed the nation for the first time in a televised speech on Friday.
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The 73-year-old renewed his "darling Mama's" promise of lifelong service as he praised her humour, warmth, and ability to see the best in people.
WATCH: King Charles III's speech in full
He also announced that he had made his son William the new Prince of Wales, with his wife Catherine the Princess of Wales – the title last used by William's late mother, Diana.
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And the father-of-two expressed his "love for Harry and Meghan as they continue to build their lives overseas".
William and Kate are the new Prince and Princess of Wales
It was one of a number of expressions of open emotion during the speech in which the King also said: "I count on the loving help of my darling wife, Camilla".
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Charles finished with an emotional sign off to his "darling Mama" when he wished: "May flights of angels sing thee to thy rest," a quote from the ending of Shakespeare's Hamlet.
King Charles III paid tribute to his beloved wife, Camilla
Royal fans were quick to react to the historic address on social media.
"I'm in tears again at the speech King Charles has just given. His love for his mother shines through…May flights of Angels sing Thee to Thy Rest," one praised.
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A second echoed: "This tweet is a little overdue, but I've just seen the magnificent, moving speech by His Majesty King Charles III. Once again, I offer my heartfelt condolences and support to the Royals."
The King remembered his "darling mama"
"I've just watched this speech from last night," a third said. "Wow. What an emotional, proud, heartfelt tribute to his mum, just a few days after she died. It was absolutely spot on, he looked & spoke like a king, I certainly had a tear in my eye, well done King Charles."
And a fourth wrote: "This was the most wonderful, emotional, promising and comforting speech a new Monarch can give. Very powerful. It left no eyes dry. He will make a very good #KingCharles. His 'darling mama' would already be very proud."
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