At 73, Charles is the oldest monarch yet to ascend the throne of the United Kingdom, following the death of his “cherished” mother at her Scottish estate of Balmoral on Thursday.
He was due to return to London from Balmoral, where the 96-year-old queen died “peacefully” after a year-long period of ill-health and decline, at the culmination of a record-breaking reign of 70 years.
“During this period of mourning and change, my family and I will be comforted and sustained by our knowledge of the respect and deep affection in which the queen was so widely held,” Charles said in a statement.
One of the planet’s most recognizable people, she was the only British monarch most people alive today had ever known.
The tributes were universal, including from Russia and China.
New York’s Empire State Building was illuminated after sunset in silver and royal purple, while the Eiffel Tower in Paris dimmed its lights in tribute.
US President Joe Biden described Queen Elizabeth as “a stateswoman of unmatched dignity”, and relayed the comforting words she gave when the United States was plunged into mourning on 9/11.
They were the same words chosen by the Daily Telegraph for its somber front-page: “Grief is the price we pay for love.”
Other British newspapers also printed special editions to mark the occasion.
“Our hearts are broken,” headlined popular tabloid the Daily Mail.
The Mirror wrote simply: “Thank you.”
Charles’s inaugural address, set to be pre-recorded, was expected to be broadcast on Friday evening, part of 10 days of plans honed over decades by Buckingham Palace and the UK government.
The new king was also expected to hold his first audience with Prime Minister Liz Truss, who was only appointed on Tuesday in one of the queen’s last official acts before her death.
Truss acclaimed the “second Elizabethan age”, five centuries after the celebrated first.
“We offer him (Charles) our loyalty and devotion just as his mother devoted so much to so many for so long,” she said in a televised address on Thursday. “God save the king.”
Charles was also due to meet officials in charge of the elaborate arrangements for his mother’s lavish state funeral, which will be attended by crowned and elected heads of state from around the world.
He will decide on the length of the royal household’s period of mourning, which is expected to last a month, while the UK government will observe at least 10 days of official remembrance, when limited business is conducted.
Gun salutes — one round for every year of the queen’s life — will be fired on Friday across Hyde Park in central London and from the Tower of London on the River Thames.
Muffled church bells will toll at Westminster Abbey, St Paul’s Cathedral and Windsor Castle, among other places, and Union flags will fly at half-mast.
Truss and other senior ministers were set to attend a public remembrance service at St Paul’s, while the UK parliament will start two days of special tributes.
The queen’s death and its ceremonial aftermath comes as the government strives to rush through emergency legislation to tackle the kind of war-fueled economic privation that marked the start of Elizabeth’s reign in 1952.