Queen Elizabeth's private secretary, Sir Edward Young, wrote a letter to the UK cabinet secretary, Sir Mark Sedwill, following the Sandringham Summit held by the Queen in January 2020, urging for continued security for Prince Harry and Meghan Markle. The letter was provided as evidence in the High Court amid Harry's current libel lawsuit against The Mail on Sunday newspaper ¹. 

The late Queen said that it was "imperative" that the Duke and Duchess of Sussex "continue to be provided with effective security" against "extremists" ¹. The letter read, "You will understand well that ensuring that the Duke and Duchess of Sussex remain safe is of paramount importance to Her Majesty and her family" ¹.

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