The 56-year-old shared photos of the "memorial tablet" on Twitter on Thursday and confirmed that English Heritage would be placing it outside the Earl's Court flat Diana lived in before marrying the Prince of Wales in 1981.
Charles wrote: "How very lovely that this blue plaque will be going up outside Coleherne Court – thank you @EnglishHeritage, for commemorating such a happy place for Diana in this way."
The plaque will read: "Diana Spencer later Princess of Wales 1961 - 1997 lived here 1979 - 1981."
Charles shared photos of the plaque being made
Diana's parents bought her 60 Coleherne Court, a property in a mansion block close to the fashionable King’s Road in Chelsea, when she settled in the capital as a young woman.
She shared the £50,000 flat with a number of girlfriends and was said to have a sign above her bedroom door which read "Chief Chick".
Diana described the few years she lived in the three-bed flat as "the happiest time of her life", according to Andrew Morton’s book Diana, In Her Own Words.
Diana lived at 60 Coleherne Court before marrying Prince Charles
Lady Diana Spencer, as she was then known, was working at Young England Kindergarten in Pimlico, central London, before she became engaged to Prince Charles.
The late Princess is the highest profile former member of the monarchy to be bestowed the honour, and was nominated by the London Assembly after the body ran a campaign asking Londoners to suggest women worthy of a blue plaque.
Anna Eavis, English Heritage’s curatorial director, said Diana's campaigns to highlight issues like HIV/Aids and landmines – and her enduring appeal as "an inspiration and cultural icon to many", were deciding factors.
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English Heritage has also announced the names of five other leading women who will be recognised with a blue plaque on properties closely associated with the individuals.
The crystallographer and peace campaigner Dame Kathleen Lonsdale's plaque will be unveiled on Thursday, 50 years after her death, at her former home in east London.
Later in the year, other monuments will be erected to fashion designer Jean Muir, anti-slavery campaigner and former slave Ellen Craft, barrister Helena Normanton and social reformer Caroline Norton.
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