Queen Elizabeth II, the head of the Commonwealth, opened the Commonwealth summit for what may be the last time on Thursday voicing hope that her son would be allowed to carry on her role.
Queen Elizabeth, who turns 92 on Saturday, welcomed leaders from the 53 Commonwealth nations - mostly former colonies - to Buckingham Palace for two days of talks that will include discussions on trade, marine protection and tackling cybercrime.
In her opening speech, Queen Elizabeth spoke of her own "extraordinary journey" as head of the Commonwealth, which started under her father King George VI with the London Declaration of 1949.
"It is my sincere wish that the Commonwealth will continue to offer stability and continuity for future generations and will decide that one day, the Prince of Wales should carry on the important work started by my father in 1949," she said, referring to her son Prince Charles.
Queen Elizabeth, who has been the group's symbolic figurehead since 1952, gave up long-haul travel in support of the biennial summit in 2013 and the 2020 gathering is set to be held in Malaysia.
On the closing day on Friday, leaders are expected to discuss who should follow Queen Elizabeth in the role.
The position is not hereditary, but Prince Charles, who is also the heir to the thrones of 16 Commonwealth nations, is expected to get the nod, despite some unease among ardent republicans.
Charles, 69, told Commonwealth leaders the body had been "a fundamental feature of my life for as long as I can remember."
"The modern Commonwealth has a vital role to play in building bridges between our countries," he said.
Maltese Prime Minister Joseph Muscat said of Charles: "We are certain that when he will be called upon to do so, he will provide a solid and passionate leadership for our Commonwealth."
British Prime Minister Theresa May, the summit host, paid tribute to Queen Elizabeth's service to the Commonwealth at the opening ceremony.
"You have been the Commonwealth's most steadfast and fervent champion," May said.
"You have seen us through some of our most serious challenges. And we commit to sustaining this Commonwealth, which you have so carefully nurtured."
A spectacle of pomp and pageantry was staged to welcome the leaders, with a guard of honour and flag bearers greeting arriving dignitaries.
More than 100 troops from the Coldstream Guards were in the honour guard, wearing their famous scarlet tunics and bearskin hats.
Born out of the former British empire, the voluntary organisation, covering a third of the world's population, typically focuses on development and democracy, but is placing greater attention on boosting trade.
During the two days of talks, the group is hoping to agree an ocean governance charter, an agenda for trade and investment, and a declaration on tackling cyber crime.
Given its highly diverse membership, if agreements can be struck within the Commonwealth, they can likely achieve wider support.
At the last Commonwealth summit in 2015, leaders struck a deal on climate change that helped pave the way for the Paris agreement days afterwards.
Friday's sessions take place at Windsor Castle, west of London, where the leaders are left entirely alone to discuss whatever they wish.