The engagement ring marks a break with the more traditional jewellery that other members of the royal family have proposed with.
Ms Ekserdjian, who is known as Ellie, is a painter and film artist, and the pair live together in London.
They first met while studying at the University of Edinburgh and have been a couple since 2021.
Her parents, Prof David Ekserdjian and his wife, Susan Moore, are said to be delighted at the news.
While Mr Chatto is not a working member of the royal family, he has occasionally joined for big ceremonial events, such as the late Queen’s funeral, the King’s Coronation and the wedding of the Duke and Duchess of Sussex.
More recently, the couple were invited to the wedding of the Princess Royal’s son, Peter Phillips, and Harriet Sperling, a former NHS nurse, which took place in Kemble last month.
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‘ Some details of this article were extracted from the following source www.telegraph.co.uk ’
