King Charles's private secretary, Sir Edward Young, has stepped down after 19 years of service to the royal family.
Sir Edward, a former banker and political adviser, joined Buckingham Palace in 2004 and served as Queen Elizabeth II's private secretary from 2017 until her death.
He then served the King as joint private secretary alongside Sir Clive Alderton — who will continue in the role alone.
Sir Edward's departure was expected after the change of reign. He had agreed to stay on until after the Coronation to help the King and his aides adjust to their new roles.
The King's private secretary is considered the most important member of the Royal Household, responsible for supporting the King in his duties as Head of State.
Described by the Royal Family as "the channel of communication between the Head of State and the Government", Sir Clive also liaises with the Armed Forces, the Church and the many organisations of which His Majesty is patron.
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Sir Clive has been a trusted and much-loved adviser to the King and Queen Consort since 2006. He moved from Clarence House to Buckingham Palace following the King's ascension.
A source in The Times describes him as "one of the most, if not the most, intelligent people I've ever met. He didn't go to university, he got fast-tracked into the Foreign Office. He broke a record and was Britain's youngest ambassador. He was the definition of a high flyer".
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Paying tribute to his colleague Sir Edward, Sir Clive said: "Edward has been an outstanding colleague and a dear friend for almost two decades.
"He made an invaluable contribution to the closing years of The late Queen's reign and to helping support the process of transition. He will be much missed by us all."
Sir Edward said: "I am honoured to have served two sovereigns through historic times, and grateful for all the support and friendship of colleagues along the way.
"I am deeply touched by their kind words and tributes as I venture beyond the Palace gates, but look forward to staying in close contact in years ahead."
It comes after King Charles made his first appearance since the coronation weekend.
On Sunday, the newly-crowned monarch took a low-key visit to Sandringham, Norfolk, driving himself to a church service at St Mary Magdalene Church.
In new photographs taken of the King behind the wheel as he drove into Sandringham, His Majesty appeared in good spirits as he smiled and waved to crowds from the window of the driving seat.
Outside the church, he warmly greeted Reverend Canon Paul Williams before the service. He wore a grey plaid suit and crisp white shirt fastened with a playful zebra-print tie.
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