Prince Harry and Meghan, also known as the Duke and Duchess of Sussex, are flying in for the queen's Platinum Jubilee celebration from the US / © AFP
The Duke and Duchess of Sussex are set to attend a cathedral service early next month as part of celebrations for Queen Elizabeth II's Jubilee year, their biographer said Friday.
Prince Harry and his wife, Meghan, stepped down from royal duties and moved to California early in 2021. Since then they have visited the UK together only once.
Omid Scobie, who co-authored a favourable biography of the couple, told reporters in London: "We'll definitely see Harry and Megan at the Thanksgiving service at St Paul's Cathedral."
The service on June 3 will be "really the first official moment" when the couple join the Platinum Jubilee celebrations, he said.
"That's really what they've been planning all along," Scobie said, calling jubilee events a "glimpse" into the royal family's future.
The service at the landmark cathedral where Harry's father wed Lady Diana Spencer in 1981 is designed to give thanks for the queen's long reign and one of the main events during four days of public celebrations.
British newspapers had reported that Harry and Meghan were likely to attend the service but Scobie's comment will be seen as confirmation, given his close links.
The queen's disgraced second son Prince Andrew -- who earlier this year settled a US civil claim for sexual assault -- is reportedly also planning to go.
Scobie said the public could witness a "special moment" of the queen meeting Meghan and Harry's two children, Lilibet and Archie, her great-grandchildren.
Lilibet -- who turns one on June 4 -- has never met her 96-year-old great-grandmother who was called the nickname when she was a girl.
He added there were rumours that Harry and Meghan would hold the christening of Lilibet in the UK, but to his knowledge, this would not happen during jubilee events.
Harry and Meghan's decision to move to north America, for privacy and financial independence, caused shockwaves through the royal family.
But it was compounded by public criticisms from the couple, including in a television interview when they accused an unnamed senior royal of racism.
The palace is bracing for more potential revelations from Harry in an upcoming autobiography.
In April, Harry and Meghan made their first joint trip to the UK since emigrating, seeing the Queen in private during a flying visit.
Scobie said Harry and Meghan "will not be out" on the balcony of Buckingham Palace alongside prominent royals on June 2 to watch the Trooping of the Colour and a flypast.
But he said they could make a "surprise appearance" on June 5, when the queen may emerge onto the balcony again with family members.
The queen has suffered recent health issues that could affect her participation in national events marking her record-breaking 70th year on the throne.
British media reported on Friday that has gone to her Scottish estate of Balmoral for a short break ahead of the celebrations.