A flag which is notorious for its ties to white supremacy and racism was seen flying on the field at a royal horse event at the King’s estate.
A Confederate Flag was flown on the field during Saturday’s evening supper at the Sandringham Horse Driving Trials.
Sophie, the Duchess of Edinburgh, also competed in the trials.
The flag was used in the American Civil War by southern states and is typically seen as a symbol of white supremacy.
Organisers of the Challenge event issued an apology following the display, saying they are “truly sorry”.
They wrote on Facebook: “We would like to sincerely apologise for the recent display of images featuring the Confederate flag.
“We now understand the significance of this symbol and the hurt and offence it represents to many people.
“We never intended to upset or cause harm, and our actions were in no way malicious or racially motivated.
“However, we recognise that intent does not lessen the impact, and we take full responsibility for this mistake. We are truly sorry and are committed to ensuring this does not happen again.”
Andrew Mountbatten-Windsor was reported to have attended the trials on Sunday.
The disgraced royal was seen by an onlooker who told The Sun that Andrew “sneaked in and out” and did not appear to want to “be seen”.
It was a rare appearance for the former prince, who was also spotted in June with a large purple bruise across his right eye and cheek.
The 66-year-old was snapped at the wheel of his car leaving Sandringham Estate with another man.
In May, he experienced a security scare, where he was allegedly confronted by a balaclava-clad man near his home.
The former Duke of York was arrested in February on suspicion of misconduct in a public office following allegations that he passed sensitive government information to paedophile financier Jeffrey Epstein.
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