The King released his first statement since being discharged from hospital on Monday – and he had an exciting announcement to make.
Charles, 75, has confirmed that another Big Help Out will take place this year, following the success of last year's event which saw seven million people volunteer as part of the coronation celebrations last May.
The King, who is not currently undertaking public duties while he recuperates from treatment on an enlarged prostate, described the event as an opportunity to build "kinder, closer communities".
His message, which was signed Charles R, was written before he underwent treatment for his benign condition.
To mark the launch of the second Big Help Out, which will be staged over three days from Friday 7 June to Sunday 9 June, the King said: "I have long believed that one of the greatest strengths of our nation is our ability to come together and help each other through times of hardship.
"Throughout my life, I have been encouraged and inspired by those selfless volunteers who dedicate their time and talents to helping others, across all communities and across the full breadth of our country."
The Prince and Princess of Wales and their children, Prince George, Princess Charlotte and Prince Louis, were among the volunteers to take part, helping out a Scout group in Slough.
The King added in his message: "It was a source of great pride to my whole family that, thanks to all these millions who took part, the coronation became a moment not just to celebrate continuity and nationhood, but also the values that we have long held dear: kindness, compassion and service to others.
"As I said in my Christmas broadcast last year, this is all the more important at a time of real hardship for many, when we need to build on existing ways to support others less fortunate than ourselves. In so doing, we also bring out the best in ourselves."
He ended by saying: "Young people’s energy and enthusiasm can be enormously valuable, and business is a vital part of the fabric of both our local communities and of our wider society.
"So, if you are able, I can only encourage you to support the Big Help Out once more, thereby helping to build the kinder, closer communities of which we can all be so proud."
Charles waved and smiled as he left the London Clinic with his wife, Queen Camilla, by his side on Monday afternoon. Watch the moment in the video below...
While Buckingham Palace did not release any further details about the nature of his medical procedure, the monarch could reportedly take up to a month off from public duties, although it is believed that he has already resumed working through his red boxes.
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