Prince Harry left for the US after attending the unveiling of Princess Diana statue in London.
The Duke of Sussex joined his brother Prince William as a new statue of their mother was unveiled at Kensington Palace on Thursday.
Queen Elizabeth was not present on the occasion as she was at Balmoral Castle in Scotland. The monarch reportedly returned to Kensington later that day but Prince Harry had already left for the airport.
British media is speculating that the Duke left without meeting his grandmother but there are not confirm reports whether Harry met the Queen.
The reports have infuriated royal fans who have criticized Prince Harry for not waiting to see the Queen.
The ceremony took place days after Prince Harry and his wife Meghan Markle named their newborn daughter after the Queen and Princess Diana.