Meghan Markle, Prince Harry, Queen Elizabeth II
Meghan Markle and Prince Harry pictured here with Queen Elizabeth II during their years as working royals. Photo: POOL / John Stillwell

Queen Elizabeth II wanted continued security for Prince Harry and Meghan Markle ahead of their move to the U.S.A. in 2020 and found it "imperative" given threats against the couple.

Her Majesty urged that the Duke and Duchess of Sussex "continue to be provided with effective security" in a letter from Buckingham Palace written on her behalf. The letter was submitted to London's High Court as evidence in the duke's current libel case against The Mail on Sunday newspaper.

"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," read the letter obtained by The Sunday Times.

It continued: "Given the duke's public profile by virtue of being born into the royal family, his military service, the duchess's own independent profile and the well-documented history of targeting of the Sussex family by extremists, it is imperative that the family continues to be provided with effective security."

The letter, written by Her Majesty's former private secretary Sir Edward Young, was sent to U.K. cabinet secretary, Sir Mark Sedwill, following the Sandringham Summit held by the Queen in January 2020. Prince Harry, Prince William and then-Prince Charles attended the meeting to discuss the Sussexes' future after they stepped back from their royal duties. Meghan Markle, during this time, was in Canada with Prince Archie.

The Duke of Sussex recalled the summit which took place on January 13 in the "Harry & Meghan" Netflix docuseries. He said he had proposed a part-time working arrangement for him and his wife but was confronted with five options.

"One being, all in, no change. Five being, all out. I chose option three in the meeting. Half-in, half-out. Have our own jobs, but also work in support of the queen," he said adding that "it became very clear very quickly, that goal was not up for discussion or debate".

He also recalled the furious outburst from Prince William calling it "terrifying" to have his brother scream and shout at him. Meanwhile, he alleged then-Prince Charles said things "that just simply weren't true" and Queen Elizabeth II would just "quietly sit there, and sort of take it all in".

Prince Harry further talked about the Sandringham Summit in his memoir "Spare" in which he admitted that his main concern at that point was for him and his family to have police protection. He was "desperate to keep security" and revealed that he even offered to personally fund for his and his family's police protection while in the U.K.