THE Prince of Wales will attend the official opening of Parliament for the first time in 17 years on Wednesday in a significant statement of his growing role supporting the Queen in state duties.
On Tuesday it was announced that the Prince would stand in for the Queen at this year's Commonwealth Heads of Government meeting (CHOGM) in Sri Lanka.
It will be the first time that the 87-year-old monarch has missed the biennial conference since 1973.
Buckingham Palace said the decision not to attend was part of a review of the amount of long-haul travel undertaken by the monarch and The Duke of Edinburgh, who will be 92 next month.
But - taken together - the moves highlight the increasingly high-profile role that Prince Charles is expected to take supporting his mother in state affairs in the coming months and years.
It will involve increasing co-ordination between the diaries of senior royals - with the Duke and Duchess of Cambridge taking on many more official duties.
David Cameron said he fully supported the Queen's decision not to attend.
"I think it's entirely understandable that she's not going to be travelling to Sri Lanka, because she is scaling down some of her international travelling, which I think is not in the least bit surprising," he said.
Apart from highlighting the Queen's age, the decision will be seen as a symbolic moment in Charles's preparation for kingship.
The Queen has always regarded her role as head of the 54-nation Commonwealth as one of her most important duties.
She has visited all but two of the Commonwealth countries and Prince Philip once described her as the "Commonwealth psychotherapist".
However, as well as the Queen's age, another factor in Prince Charles deputising for his mother may be concerns about his future role.
Some Commonwealth countries are questioning whether the Prince of Wales should automatically become head of the group when he becomes king.
The Prince feels strongly that the role should be his, and his presence at the meeting as the Queen's representative would only strengthen his case.
A Buckingham Palace spokesman said that the CHOGM decision did not mean that the Queen would not carry out any future foreign trips but accepted they would be restricted.
"Any long-haul trips will be looked at on a case-by-case basis," he said.
The spokesman compared the decision to last year's arrangements for the Diamond Jubilee. Other members of the Royal Family carried out overseas engagements.
The Palace said the announcement of the Prince of Wales attending the State Opening of Parliament at the same time as the CHOGM announcement was "coincidental".
But it added: "Members of the Royal Family have always supported the Queen in her work. The Prince of Wales is expected to play a significant role in this."
The Queen and The Duke of Edinburgh will also attend the opening of Parliament on Wednesday.
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