King Charles III has praised the Queen’s “unequalled reign” after being proclaimed king at a ceremony at St James’s Palace.
The King became the monarch after the death of his mother, but a meeting formally confirmed it on Saturday.
He also approved the day of the Queen’s funeral, Monday, 19 September, being a bank holiday.
Speaking before the Accession Council, the King said his mother’s death had been an “irreparable loss”.
Meanwhile, senior MPs in the House of Commons, including Prime Minister Liz Truss, swore allegiance to the new monarch.
Making his address in the State Apartments of St James’s Palace in London, King Charles said: “It is the greatest consolation to me to know of the sympathy expressed by so many to my sister and brothers and that such overwhelming affection and support should be extended to our whole family in our loss.”
He later spoke of the Queen’s “selfless service”, saying: “My mother’s reign was unequalled in its duration, its dedication and its devotion.
“Even as we grieve, we give thanks for this most faithful life.”
The King added he would “strive to follow the inspiring example” he was set by his mother in taking on the “heavy responsibilities of sovereignty”.
It is the first time the historic ceremony, which dates back centuries, has been televised.
<<BBC>>