Prince Harry is believed to have arrived back on British soil at the weekend ahead of Prince Philip's funeral.
The 36-year-old royal is believed to have flown into Heathrow airport on a British Airways flight from Los Angeles at 1.15pm on Sunday.
The Sun newspaper reports that Harry was greeted by police and security and escorted in a Range Rover to Kensington Palace.
Harry, who was not joined by his wife, Duchess Meghan - who was advised not to travel because she is heavily pregnant with the couple's second child - doesn't have to spend 10 days in quarantine on "compassionate grounds" for his grandfather's funeral.
However, he would have been required to have received a negative Covid-19 test result to enter the UK.
Harry and his brother Prince William, 38, will be reunited for the first time since Harry relocated to the US with Meghan when the couple stepped down as senior royals last year as they commemorate the life of The Duke of Edinburgh, who died at the age of 99 on Friday.
The siblings are expected to stand "shoulder to shoulder" at the Windsor Castle service.
The Royal Family is hopeful that the pair will be able to put aside their reported rift as they honour Prince Philip, who was said to have been "dismayed" by the apparent breakdown of the relationship between the brothers towards the end of his life.
Royal insiders said at the weekend: "He urged them both to put to rest their differences and be mindful of their duty to the Queen and the country".
William and Harry will also come face-to-face for the first time since the tell-all interview he and Meghan gave to chat show host Oprah Winfrey last month.
During the conversation, Harry claimed that both William and his father Prince Charles, were "trapped" by their responsibilities to the monarchy, although a friend close to The Duke of Cambridge claimed that Harry's comments were "way off the mark" as William, takes a similar approach to his grandmother, Queen Elizabeth, about his role.
The insider said: "He had a path set for him and he's completely accepting of his role.
"He is very much his grandmother's grandson in that respect of duty and service."