The Duke of Sussex has attended his father's Coronation, sitting with non-working members of the royal family at Westminster Abbey.
The prince arrived alone without his wife Meghan and left immediately afterwards.
He was seated two rows behind the Prince of Wales for the service.
The BBC understands he was not invited to appear on the Buckingham Palace balcony and it is thought he has since headed to Heathrow airport.
It is the first time he has been seen at an event with his family since his controversial memoir, Spare, was published.
Prince Harry was seen getting into a car alone shortly after the service had finished.
On the Buckingham Palace balcony hours later the King and Queen were joined by other members of the royal family, including the Prince and Princess of Wales.
Prince Andrew left Westminster Abbey in a car behind, with Princess Eugenie and her husband.
Prince Harry has arrived at Westminster Abbey ahead of the coronation of his father, King Charles III https://t.co/zwSW1otXwi pic.twitter.com/b7oFiU3apd
— BBC News (UK) (@BBCNews) May 6, 2023
Earlier, when Prince Harry entered the abbey, dressed in a morning suit and wearing medals, he appeared relaxed and was seen smiling at guests as he walked down the nave of the abbey, before chatting to several family members.
He tapped Princess Beatrice's husband Edoardo Mapelli Mozzi on the back with a smile on his face, before taking his place beside Jack Brooksbank - husband of Princess Eugenie - in the third row. Also in the third row was the Duke of York, Prince Andrew.
He watched the ceremony behind the King's sister Princess Anne and the Duke of Kent, Queen Elizabeth II's first cousin, dressed in Garter robes on the second row.
Ahead of them were the Prince and Princess of Wales and their children Princess Charlotte and Prince Louis, as well as the King's brother the new Duke Edinburgh - Prince Edward - and his wife Sophie.
The young Royals are sitting between their parents as they watch their grandfather King Charles's Coronation
— BBC News (UK) (@BBCNews) May 6, 2023
Previously, Prince Harry had been seated in the second row - directly behind the King - at Westminster Abbey for the late Queen Elizabeth's funeral last year.
The prince was seen in television footage watching intently as the archbishop raised St Edward's Crown above his father's head during the Coronation.
Later, when the congregation paid homage to the new monarch, Prince Harry was seen along with other royals saying the words: "God save King Charles. Long live King Charles. May the King live forever."
After landing at London's Heathrow Airport on Friday morning, the prince reportedly stayed at Frogmore Cottage on the grounds of Windsor Castle - the residence he and Meghan were asked to vacate by the King.
His wife, the Duchess of Sussex, has remained in Los Angeles with their children, where their son Prince Archie will be celebrating his fourth birthday.
A source told the US outlet Page Six that Prince Harry intended to make "every effort to get back in time for Archie's birthday".
Last month, Buckingham Palace confirmed Prince Harry would attend the ceremony alone.
However, officials said Prince Harry and his uncle Prince Andrew would have no formal role in the ceremony, as they are not working members of the royal family.
Unlike other members of the family, Prince Harry did not wear robes or military uniform - despite the fact that he served in the army for a decade, including two tours of Afghanistan.
Meghan stays in the US
Relations between Prince Harry and other members of the family have been strained since his memoir was published.
The book vividly revealed fall-outs and disagreements with relatives, and he has since spoken of feeling "different" from the rest of his family.
The decision for Meghan to reject the invitation was widely seen as part of these continuing, unresolved family tensions.
And last month it was revealed that the King tried to stop Prince Harry taking legal action against newspapers over alleged phone-hacking.
In a witness statement revealed by court papers, Prince Harry said he was "summoned to Buckingham Palace" and told to drop the cases because of the effect on the family.
- BBC