The essential
Queen Elizabeth II died "peacefully" on Thursday at the age of 96 at her Scottish residence in Balmoral.
She had been placed under surveillance a few hours earlier, her doctors saying they were "concerned" about her state of health.
His son Charles, 73, becomes King Charles III, while the latter's wife, Camilla, becomes queen consort.
The new king is due to return to London on Friday and address his subjects for the first time in a pre-recorded message broadcast in the evening.
He is to be officially proclaimed king on Saturday.
The death of the sovereign opens a period of national mourning, until her funeral in ten days.
During the day, 96 cannons will be fired from several places in the country and the bells of St. Paul, Westminster Abbey and Windsor Castle will ring.
Addressing "their thoughts" to the royal family and its people, heads of state or government have multiplied their tributes.
In 70 years of reign, Queen Elizabeth has met almost all the major leaders of the planet.
05:51
Charles III will address his subjects for the first time
Once back in London with Camilla, now queen consort, the new king will address the British for the first time on television, in a message recorded in advance and broadcast in the evening.
He must also meet with Prime Minister Liz Truss, whose enthronement by Elizabeth II on Tuesday was the last constitutional act of a life dedicated to her role to the end.
05:45
Good morning !
And welcome to this live as the UK, like the world, mourns Queen Elizabeth II, who died yesterday.
You will be able to follow the latest events and tributes in our company.