According to the Daily Telegraph, the letter was sent to Charles, who was then Prince of Wales, following Harry and Meghan’s appearance on the Oprah Winfrey Show in March 2021.
In the interview, Meghan claimed a member of the royal family had speculated about how dark their unborn son’s skin would be.
The newspaper’s source claimed the exchange is part of the reason why Meghan is not attending the coronation on May 6, saying she feels she did not receive a satisfactory response to her concerns.
A spokesperson for Meghan said: “The Duchess of Sussex is going about her life in the present, not thinking about correspondence from two years ago related to conversations from four years ago.
“Any suggestion otherwise is false and frankly ridiculous. We encourage tabloid media and various royal correspondents to stop the exhausting circus that they alone are creating.”
The paper had reported Meghan’s letter was sent in response to a letter from Charles, in which he expressed his sadness over the split within the family.
The letters are also said to make clear the identity of the senior royal who made the comment, with both Meghan and Charles acknowledging the remark was not made maliciously, according to the paper.
The claims in March 2021 plunged the monarchy into crisis as the Windsors faced allegations of racism.
Since the Oprah Winfrey interview, Harry has denied the couple accused members of the royal family of being racist.