The leaders of the Commonwealth will later meet behind closed doors to discuss whether the Prince of Wales should replace his mother as leader of the 53-nation body.
On Thursday, the Queen voted Prince Charles as the future leader of Commonwealth Heads of Government Meetings (CHOGM) at Buckingham Palace
She said it was her "sincere desire" that he "one day" take over.
But the role is not hereditary and will not automatically pass to the Prince of Wales The Queen's Death
The leaders are expected to approve the move when they meet at Windsor Castle, but there is no confirmation whether there will be an announcement after the meeting.
The BBC's diplomatic correspondent, James Landale, said some suggestions that the position in the member states should be rotated.
Meanwhile, South African President Cyril Ramaphosa has suspended his attendance at the London Summit to deal with violent protests at home
C lashes have taken place in the Northwest Province, where demonstrators are calling for jobs, housing and an end to corruption.
- "No other options" for Commonwealth chief
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Opening Summit On Thursday, the Queen said: "It is my sincere desire that the Commonwealth continue to be stable and secure Continuity for future generations and that one day the Prince of Wales will continue the important work that my father started in 1
The Office's President, Maltese Prime Minister Joseph Muscat, told the delegates, "We are sure that if asked, he will take a solid and passionate leadership for our Commonwealth." [19659007PrimeMinisterTheresaMayandCanadianPrimeMinisterJustinTrudeauhavePrinceCharles
Other topics discussed at the two-day summit are marine protection, cyber security and trade between countries.
The ceremony is attended by 46 Commonwealth leaders from the 53 Member States, with the remaining participants being Foreign Ministers.
The Commonwealth represents about 2.4 billion people, but critics say the organization is so different it is struggling to know what it is for, said BBC Royal Correspondent Jonny Dymond
What is CHOGM
- The Commonwealth Heads of Government meeting – or CHOGM – is usually held every two years
- It is attended by presidents and prime ministers from the 53 member countries – as well as their family members, lobbyists and journalists
- This year it will be held in London held and the last meeting – 2015 – took place in Valletta, Malta
- The last CHOGM took place in the Pacific island nation of Vanuatu in 2017 – but cyclone Pam ravaged the country for two years earlier
- At the end of two days of deliberations vote the leaders usually make a communique on an important topic too