Commonwealth chiefs planning for post-queen future
The Commonwealth has begun secret discussions to decide who will succeed Queen Elizabeth as its head.
Although Prince Charles will be crowned king of the UK on the death of his mother, the head of the Commonwealth is not a hereditary position.
A "high-level group" of Commonwealth officials are set to meet in London.
The agenda for the all-day summit says there will be a discussion of "wider governance considerations", which insiders say is code for the succession.
A senior source said: "I imagine the question of the succession, however distasteful it may naturally be, will come up."
The queen turns 92 in April. She was proclaimed head of the Commonwealth at her coronation when she became head of state in seven of its eight members.
Today it has 53 members, mostly former constituents of the British Empire.
It is not a hereditary position that will pass automatically to the Prince of Wales, who will be head of state in only 15 of the member nations.
Any decision about the future would have to be made by the Commonwealth heads of government at the time of the queen's death, but there is no formal process for choosing her successor.
While many Commonwealth figures presume there will be no realistic alternative to Charles, there has in the past been talk of electing a ceremonial leader to improve the organisation's democratic credentials.
According to documents seen by the BBC, the high-level group will not just confine itself to bureaucratic changes.
The agenda for the meeting is reported to say: "Discussions will take into consideration the issues raised in the first session and also the wider governance considerations of the Commonwealth."
Although Prince Charles remains the most likely person to succeed his mother, some states have discussed electing a president instead.
A 2009 diplomatic cable sent to Washington - later released by WikiLeaks - revealed some concerns about his suitability to lead the grouping.
Amitav Banerji, Commonwealth secretariat director of political affairs, reportedly told a US embassy political officer in London that the prince "does not command the same respect" as the queen.
The group could decide to endorse him as a one-off decision or agree a new constitution that would automatically place the British head of state as Commonwealth head, the BBC reported.
Prince Charles represented his mother at the last meeting in Sri Lanka in 2013.
The high-level Commonwealth officials who are due to discuss the matter are its chairman Anote Tong, former president of Kiribati; Lord Howell, former British energy secretary; Louise Fréchette, former United Nations deputy secretary general; Robert Hill, former Australian defence minister; Dame Billie Miller, former deputy prime minister of Barbados; Dr Ngozi Okonjo-Iweala, former Nigerian minister of finance; and George Vella, former deputy prime minister of Malta.