Wreaths will be laid to honour the RBL, which was formed 100 years ago at 09:00 BST on Saturday.
The Prince of Wales has paid tribute to the “life-changing and often life-saving support” the Royal British Legion (RBL) provides to the Armed Forces, in a video message honouring the charity’s 100th birthday.
Prince Charles said the RBL provided a “constant and reassuring presence” and an “unending commitment”.
The RBL was formed exactly 100 years ago at 09:00 BST on Saturday.
Wreathes will be laid at the Cenotaph in London and other parts of the UK.
Prince Charles said he had the “utmost admiration” for the RBL’s ability to rally support for the Armed Forces and help grieving families.
“There are few organisations which hold a place at the heart of society in the way the RBL does,” he said.
“For 100 years, the RBL has been a constant, through the annual Poppy Appeal, leading the nation in remembrance, and providing a life-long commitment to every veteran and their families.”
He offered his “sincere and heartfelt gratitude” to those who helped build the charity.
“Those who have served have an organisation that provides life-changing and often life-saving support, an organisation that speaks up on their behalf and an organisation that ensures their sacrifices shall never be forgotten,” he added.
Other celebrity supporters to pay tribute to the RBL include Ross Kemp and Stephen Fry.
Charles Byrne, the RBL’s director general, said: “We remain committed to our mission to ensure that those who have given so much for their country get the fair treatment, support and recognition they deserve.”
