Buckingham Palace has been forced to delete a tweet containing Charles' first statement as King following the death of the Queen at age 96.
The statement from King Charles mourned the death of his "beloved" mother and said it was a time of great sadness for him and other members of the royal 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 across the world."
Not long after the statement was posted, however, the Palace deleted it due to a typo in the tweet sharing King Charles' words.
Instead of saying, "A statement from His Majesty the King", Buckingham Palace tweeted, "His Majesty His King".
The post was swiftly deleted and the statement with the correct caption was uploaded.
Many people left tributes for the Queen on the statement, with one saying she was "truly an inspiration".
"I will always remember her as the most remarkable woman full of grace, dignity yet most caring and genuine at the same time," one mourner tweeted.
"It is the end of an era, such a great woman."
King Charles has given himself the title King Charles III, following tradition from the Queen's father Albert, affectionately known as Bertie, who became King George VI in deference to his father King George V.
Charles' wife, Camilla, the Duchess of Cornwall, will be known as Queen Consort – a title that came with Queen Elizabeth II's blessing after years of contention, dating back to the days before she even married Prince Charles.
It was not always a given that the 75-year-old Camilla would take the title, even though it gives her none of the sovereign's powers.
While the wife of a king is traditionally crowned queen, the question of what title Camilla would hold when Charles became king had been a tricky one for many years due to the sensitivity about her status as his second wife.
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