The Queen will say that members of the Commonwealth are "guardians of a precious flame", in her Commonwealth Day radio message on Monday. Her Majesty will address the 53 nations to say that what they share is more important now than at any point in its history.
She will warn the Commonwealth that "when common goals fall apart, so does the exchange of ideas. And if people no longer trust or understand each other, the talking will soon stop too."
The Queen will continue to say that there are "huge advantages" to being a part of the Commonwealth and discuss the future of the association, which began over 65 years ago.
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The Queen will address the Commonwealth on Monday
"We are guardians of a precious flame, and it is our duty not only to keep it burning brightly but to keep it replenished for the decades ahead," she will say.
The message, which was recorded in the Regency Room at Buckingham Palace, will have the theme of A Young Commonwealth. The Queen will advise that the Commonwealth can only flourish "if its ideas and ideals continue to be young and fresh and relevant to all generations".
She will cite the success of the 2014 Commonwealth Games in Glasgow as an example of "youthfulness and vitality", and credit the Commonwealth as a "globally diverse and inclusive community".
The Queen will attend the Commonwealth Day service at Westminster Abbey
The message will also be broadcast at Westminster Abbey, where the Queen will join 2000 people, including representatives from Commonwealth countries, for the annual Commonwealth Day service.
Her Majesty will be joined by the Duke of Edinburgh, Prince Charles and Camilla for the service. Prince William and the Duchess of Cambridge, née Kate Middleton, will also attend.
The Queen and Prince Philip will later attend the Commonwealth Day reception at Marlborough House, home of the Commonwealth Secretariat. They will be there as guests of the Commonwealth Secretary-General, Kamalesh Sharma.