The 87-year-old Queen Elizabeth II will skip the Commonwealth heads of government meeting in Sri Lanka this fall - the first time she's missed the biennial gathering since 1971.
The queen has long been a major supporter of the 54-nation Commonwealth. Her decision, announced today, to send Prince Charles to the November 15-17 meeting in Sri Lanka appears to be part of efforts to reduce her long-distance journeys.
It will also allow her to avoid attending the controversial summit, which has been under fire by rights activists concerned about Sri Lanka's wartime record of alleged abuses.
The monarch was briefly hospitalized for a stomach illness earlier this year, and did not attend the Commonwealth Day Observance service at Westminster Abbey on March 11. She has rarely taken time off for illness, having carried out more than 400 official engagements in 2012 - ranging from private meetings with the prime minister to ceremonial gatherings.
The Commonwealth summit brings together dozens of presidents and prime ministers from Britain's former colonies - many of which were part of the British empire in the queen's youth.
Her father King George VI was emperor of India and the organization means a great deal to her, said Philip Murphy, director of the Institute of Commonwealth Studies and a professor at the University of London.
The queen missed the meeting in Singapore in 1971 amid a heated debate over Britain's proposal to sell arms to South Africa.
Rights groups and some governments have called for an international probe into the alleged wartime abuses in Sri Lanka's long civil war, which ended in 2009. Canada's prime minister has opted not to attend the meeting.
The New-York based Human Rights Watch has argued for a change of venue unless the Sri Lankan government "makes prompt, measurable and meaningful progress on human rights."
Although the queen's decision does not aim to make a political statement, it will allow her to graciously sidestep the controversy, Murphy said.
"I think people who are disturbed by the (summit) being held in Colombo will take great solace in this announcement," he said Tuesday.
Charles attended the 2007 Uganda Commonwealth summit with his mother but going in her place this time is seen as a big step.