The monarch, 73, expressed his gratitude to everyone who had shared messages of "condolence and support" following the sad death of Her Majesty aged 96 on September 8. King Charles added that he and Queen Consort Camilla had been left "deeply touched" by the outpouring of love and support during the royal family's "time of grief".
WATCH: King Charles III surprises royal fans in Queen's lying in state queue
In a written message issued by Buckingham Palace, Charles said: "Over the last ten days, my wife and I have been so deeply touched by the many messages of condolence and support we have received from this country and across the world.
"In London, Edinburgh, Hillsborough and Cardiff we were moved beyond measure by everyone who took the trouble to come and pay their respects to the lifelong service of my dear mother, the late Queen.
"As we all prepare to say our last farewell, I wanted simply to take this opportunity to say thank you to all those countless people who have been such a support and comfort to my Family and myself in this time of grief."
The King thanked supporters for their messages of 'condolence and support'
On Monday, Charles will lead the nation in mourning for its longest reigning monarch at the state funeral for the Queen at Westminster Abbey.
Two thousand people including international royals and world leaders will come together for a day of pageantry and military processions to remember the late Queen.
The outpouring of love has been a comfort during this 'time of grief'
King Charles' emotional statement comes after a busy day for the monarch, which saw him hold an audience with new Prime Minister Liz Truss before attending a special reception for visiting heads of state at Buckingham Palace.
The King and Queen Consort hosted world leaders and official overseas guests at the palace, joined by senior members of the royal family including the Prince and Princess of Wales.
On Saturday, King Charles joined his son Prince William for a surprise walkabout to greet royal supporters in the queue to see the Queen lying in state.
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