The Prince of Wales wore the cypher of both Queen Elizabeth II and King Charles III at the coronation.
According to reports, this makes Prince William the first since Lord Mountbatten to be appointed by multiple monarchs as Aide-de-camp.
But no formal announcement was made regarding the cypher and the role given to the Prince of Wales.
Charles III was crowned monarch of the United Kingdom and 14 Commonwealth realms on Saturday at Britain's first coronation for 70 years, during a ceremony steeped in a millennium of ritual and spectacle.
Charles, 74, became the oldest sovereign yet to be crowned at London's Westminster Abbey, after a lifetime as heir to his late mother Queen Elizabeth II.
Prince Harry, who has criticised the family since leaving for the United States in 2020, attended the coronation on his own.
Harry left the UK just very shortly after the end of the ceremony, determined to be back in California on the same day his son Archie turned four, The Sun daily reported on its website.
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