Prince Harry reportedly travelled to the UK on a commercial American Airlines flight yesterday morning.
The Duke of Sussex departed from Los Angeles and landed at Heathrow Airport in London at 11.23am on Friday.
Passengers were said to be gobsmacked at seeing Harry on American Airlines flight AA136 as he jetted into the UK for a short visit to attend his father's Coronation today.
His wife Meghan Markle stayed in California with the couple's two children, Prince Archie and Princess Lilibet, as today is also their son's fourth birthday and she will be celebrating with him.
Harry is also rumoured to return to the US shortly after the ceremony at Westminster Abbey so that he can arrive home in time to still celebrate Archie's special day.
At the Coronation, the King's younger son will not wear his military uniform or robes.
The Duke of Sussex served in the Army for a decade and did two tours of Afghanistan but will not be allowed to adorn the military uniform because he is no longer a working royal.
The same rules applied when Charles' youngest son and Prince Andrew wore morning suits for Queen Elizabeth II's funeral last September.
Charles allowed Harry and Andrew to wear the uniform "as a special mark of respect" at the final vigil for the late Queen at Westminster Hall ahead of the funeral service.
The Duke made no specific requests concerning his outfit for the Coronation but was willing to wear whatever was asked of him, sources told the Telegraph.
It is reported that Harry will be relegated to the third row during the service at Westminster Abbey which will enthrone King Charles and Queen Camilla.
It is said he will sit between Princess Eugenie's husband Jack Brooksbank and Princess Alexandra - the cousin of the late Queen, who hasn't had a working royal engagement in a decade.
A source told The Sun: "There were discussions that the seating could be arranged on line of succession.
"But that would have put fifth-in-line Harry front and centre — and with William and Kate.
"Instead the decision was working royals only at the front and work back from there. Harry will be a long way from his father."
It comes as the Order of Service today's Coronation of King Charles and Queen Camilla was revealed, confirming there will be no role for Prince Harry.
The lengthy programme for the ceremony, which begins just before 11am at Westminster Abbey, shows which royals will be taking part in processions - as well as confirms the other key players taking prestigious roles later today.
The first sight of Charles and Camilla looks set to be around 10.20am when they travel in the Diamond Jubilee state coach to the Abbey from Buckingham Palace.
Members of the Royal Family are set to arrive at the Abbey from just after 10.35am to take their seats, while the Prince and Princess of Wales with their children Prince George, Princess Charlotte and Prince Louis will arrive minutes later and take their seats.
The main procession into the Abbey by the King and Queen will begin just before 11am - when clergy will walk through the church along with those picked to carry in the Coronation regalia.
