The King paid a loving tribute to his late mother as he marked the first full day of mourning with an address to the nation and a walkabout in front of Buckingham Palace.
The new monarch received the heartfelt condolences and kisses from the public when he arrived at the palace after spending Thursday night at Balmoral.
“Thank you for your love and devotion to our family and to the family of nations you have served so diligently all these years. May flights of angels sing thee to thy rest.”
In the afternoon, the death gun salute was fired at 1pm across the UK and abroad, made up of 96 rounds to represent each year of the Queen’s life.
The King held the first of what will be many audiences with the Prime Minister. It was just three days ago that Liz Truss was asked to form a government by the Queen at Balmoral, in one of her final official duties.
The lyrics to the national anthem have changed from “Queen” to “King” and “her victorious” to “him victorious”.
French President Emmanuel Macron expressed “deep sadness” and a sense of “emptiness” as he praised her “great affection for France” and recalled in a video message that she mastered “our language, loved our culture and touched our hearts”.
There were tributes from UK politicians too, with both tears and laughter in the Commons, particularly when Theresa May recounted a dicey moment where she dropped some cheese in front of the Queen during a picnic at Balmoral.
“We all mucked in to put the food and drink out on the table. I picked up some cheese, put it on a plate and was transferring it to the table. The cheese fell on the floor. I had a split-second decision to make.
“I picked up the cheese, put it on the plate and put it on the table. I turned round to see that my every move had been watched very carefully by Her Majesty the Queen. I looked at her. She looked at me and she just smiled. And the cheese remained on the table.”
Then Charles holds his first Privy Council, accompanied by his Queen and William, who are also Privy Counsellors, and makes his personal declaration and oath.
The first public proclamation of the new sovereign is read in the open air from the Friary Court balcony at St James’s Palace by the Garter King of Arms. Proclamations are then made around the city and across the country.
Union flags go back up to full-mast at 1pm and remain there for 24 hours to coincide with the proclamations before returning to half-mast.
Charles will also hold audiences with the Prime Minister and the Cabinet.