In a small moment of history the Queen has, for the first time, publicly referred to the day when she will no longer reign over us.
It came as Her Majesty welcomed Prime Ministers and Presidents from six continents to the Commonwealth Heads of Government Meeting (CHOGM) in London - an organisation she has led for 65 years.
When her tenure began there were just eight member countries.
“Who then would have guessed that a gathering of its members states would one day number 53 or that it would comprise 2 point 4 billion people,” Queen Elizabeth II told the crowd of world leaders at Buckingham Palace.
Two days shy of her 92nd birthday, the Queen has turned her mind to who should replace her as figurehead of the family of nations when she dies. The title Head of the Commonwealth is an honorary, not hereditary, position and there have been calls for it to go to someone other than Prince Charles.
Britain’s Labor Opposition leader Jeremy Corbyn said that after the Queen, Commonwealth countries should get to decided “who its president is on a rotational basis”
That’s not a view shared by Queen Elizabeth.
“It is my sincere wish that the Commonwealth will continue to offer stability and continuity for future generations that one day the Prince of Wales will carry on the important work started by my father in 1949,” she said.
It was a surprisingly blunt statement from the Queen, and one leaders will find hard to ignore when succession is discussed at a private retreat at Windsor Castle on Friday.
There has been a long running, but subtle, campaign to get Prince Charles the job since the last Commonwealth meeting in Malta two years ago.
The Conservative British Government has thrown its weight behind the Prince of Wales as has Australia
Prime Minister Malcolm Turnbull said both major parties supported the role passing to the Prince.
“The Australian Government's position, is that the head of the Commonwealth should continue to be the King or Queen of the United Kingdom,” Mr Turnbull said.
The Queen will continue to hold the title until she dies or abdicates but it has wearied her. Her Majesty has signalled she will no longer be travelling the vast distances between the old imperial dominions.
British Prime Minister Theresa May recieved sustained applause when she paid tribute to the Queen.
“You have seen us through some of our most serious challenges,” Mrs May said.
“And we commit to sustaining this Commonwealth, which you have so carefully nurtured. For your service, for your dedication, for your constancy – we thank you”.