The Queen delivered a touching video message at the COP26 evening reception after being rendered unable to attend.
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Following an introduction by Jamaican Prime Minister Andrew Holness, the Queen appeared to the attendees and spoke about the importance of addressing climate change and the COP26 Summit's need.
She also reminisced about her late husband, Prince Philip, the Duke of Edinburgh, saying: "This is a duty I am especially happy to discharge, as the impact of the environment on human progress was a subject close to the heart of my dear late husband, Prince Philip, The Duke of Edinburgh."
WATCH: The Queen pays tribute to Prince Philip during COP26 address
Her Majesty quoted one of his speeches from 1969, before taking the moment to also share her pride in her son Prince Charles, the Prince of Wales, as well as Prince William, the Duke of Cambridge.
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The Queen delivered a touching video message
"It is a source of great pride to me that the leading role my husband played in encouraging people to protect our fragile planet, lives on through the work of our eldest son Charles and his eldest son William. I could not be more proud of them," she added.
On medical advice, Her Majesty's recent appearances have all been virtual
The Queen ended her speech on a poignant note, as she said: "Of course, the benefits of such actions will not be there to enjoy for all of us here today: none of us will live forever.
"But we are doing this not for ourselves but for our children and our children's children, and those who will follow in their footsteps."
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Following a stay at the hospital last month, the Queen cancelled a two-day visit to Northern Island and was advised to rest for two weeks.
The Queen drove solo around her Windsor estate
The monarch was recently pictured for the first time in public as she was seen driving her Jaguar car in the grounds of Windsor Castle on Monday, as the senior royals attended events at the COP26 summit in Glasgow.
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