Prince Harry celebrated the 10th anniversary of the Invictus Games at an event in London, but the royal family was not in attendance.

On Wednesday, the 39-year-old Duke of Sussex marked the tournament’s milestone during a service of thanksgiving held at St. Paul’s Cathedral, the church where his parents, King Charles III and the late Princess Diana, married in 1981. 

In 2014, Harry founded the Invictus Games, a multi-sport event for wounded, injured and sick servicemen and women. The first Invictus Games were held in September 2014 at London’s Queen Elizabeth Olympic Park.

Meanwhile, Charles and senior royal family members attended a garden party at Buckingham Palace two miles away after it was announced that the monarch would not be able to meet with his son while Harry is in the U.K.

PRINCE HARRY WON’T MEET WITH KING CHARLES DURING TRIP TO UK FOR INVICTUS GAMES ANNIVERSARY

At Buckingham’s first garden party of the season, Charles was joined by Queen Camilla; Anne, Princess Royal; Prince Edward, Duke of Edinburgh; Sophie, Duchess of Edinburgh; Birgitte, Duchess of Gloucester; and Prince Richard, Duke of Gloucester. Ahead of the garden party, Charles held his weekly audience with U.K. Prime Minister Rishi Sunak.

Charles’ son Prince William and his wife Kate Middleton did not attend the garden party. The Prince of Wales, 40, conducted an investiture ceremony at Windsor earlier on Wednesday while the Princess of Wales, 41, is taking time off from official royal duties while she undergoes cancer treatment.

However, Harry’s uncle, Charles Spencer, the 9th Earl Spencer and Diana’s younger brother, attended the Invictus Games’ anniversary service in support of his nephew.

Harry read a Bible passage at the service of thanksgiving at St. Paul’s Cathedral. (Samir Hussein/WireImage)

At the service, Harry read a passage from the Bible, and “Homeland” star Damien Lewis recited William Ernest Henley’s “Invictus” poem, per the BBC. The service was led by the Dean of St. Paul’s, The Very Reverend Andrew Tremlett.

The Duke of Sussex will attend multiple events while in London to commemorate the Invictus Games’ 10th anniversary. 

On Tuesday, Harry was part of an onstage panel during The Invictus Games Foundation Conversation titled “Realising a Global Community” at the Honourable Artillery Company.

Harry will be in the U.K. for three days before being joined by his wife Meghan Markle for a trip to Nigeria after the couple were invited to visit the African country by its Chief of Defense Staff.

Charles was joined by Queen Camilla and other senior royals. (Jordan Pettitt – Pool/Getty Images)

On Tuesday, a representative for Harry confirmed to Fox News Digital that Charles wouldn’t be able to meet his son during his U.K. trip.

“In response to the many inquiries and continued speculation on whether or not The Duke will meet with his father while in the UK this week, it unfortunately will not be possible due to His Majesty’s full programme,” the spokesperson said.

“The Duke of course is understanding of his father’s diary of commitments and various other priorities and hopes to see him soon.” 

King Charles recently returned to public duties amid his cancer battle. 

Harry will not meet with Charles during his trip to the U.K. (Samir Hussein/WireImage)

Shortly after Charles’ cancer diagnosis was announced in February, Prince Harry flew over 5,000 miles from California to the U.K. to visit his father.

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However, Prince Harry’s trip to England at that time was short, according to royal experts. The Duke of Sussex reportedly only stayed in the U.K. for 24 hours, during which he met with Charles for 45 minutes at Clarence House. The Duke of Sussex didn’t meet with William during the trip.

Charles recently returned to public duties amid his cancer battle. (Jordan Pettitt – Pool/Getty Images)

“I spoke to him,” Harry later told “Good Morning America” about his meeting with Charles. “I jumped on a plane and went to go see him as soon as I could.”

“Look, I love my family,” he added. “The fact that I was able to get on a plane and go and see him and spend any time with him, I’m grateful for that.”

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