The Duke of Sussex and Prince of Wales made separate addresses to honour those working to further their mother’s legacy at the Diana Legacy Award.
The brothers avoided each other, with William appearing in person for the ceremony and Harry speaking to the young people present afterwards via a livestream.
William attended the event at the Science Museum in London on Thursday night and gave a speech to mark the charity’s 25th anniversary.
Harry addressed those in the audience via a live video for about half an hour after the ceremony concluded.
Harry said: “Thank you very much for inspiring so many others and at the same time protecting my mother’s legacy, I really appreciate that.
“And Tessy (Ojo, chief executive of the Diana Award), again, well done on this fantastic group of individuals.”
William earlier said that his mother taught him that “everyone has the potential to give something back”.
William took to the stage to AC/DC’s song Thunderstruck, telling the audience that he and his wife, the Princess of Wales, have sought to focus on Diana’s legacy through their work.
“This evening’s Legacy Award is particularly special as it marks the 25th anniversary year of The Diana Award, a charity set up to reflect my mother’s belief that young people can change the world,” he said.
“I know that she would have been honoured to see a charity in her name doing such inspirational work to uplift young people from all corners of the globe.”
He said that his mother taught him that “everyone in need deserves a supporting hand in life”.
“She taught me that everyone has the potential to give something back; that everyone in need deserves a supporting hand in life,” he said.
“That legacy is something that both Catherine and I have sought to focus on through our work, as have the 50,000 young people who have received a Diana Award over the past 25 years.
“I am so proud to see this belief of my mother’s manifested in the amazing young people receiving the Legacy Award tonight.”
After presenting the awards, William met the winners and told them: “The breadth of what you all cover, I’m amazed.”
He added: “I’m so blown away by everything you’re doing, because you’re doing it alongside your studies, your lives, your families, everything else.
“There are a lot of barriers I’m sure a lot of you are facing every time you’re doing this.”
William also addressed his walk-on song choice.
“I like AC/DC, that’s George’s song,” he said.
After the prince left, Chiara Riyanti Hutapea Zhang, 18, who won an award for her charity Cases 4 Care’s work with undocumented children, said that meeting him was “like a dream come true”.
“He was really nice and welcoming,” she said.
She said that winning the award was “a once-in-a-lifetime opportunity” but it also felt like “the beginning of something new”.
Joel Nkeonye Mordi, 26, who won an award for founding a LGBT+ youth charity in Nigeria, said that it was “such a huge honour”.
He added: “It’s a call to action.”
The royal brothers have continued to distance themselves from each other in recent months.
The pair did not meet when Harry spent time with the King at Clarence House following news of his cancer diagnosis last month.
In an interview with a US breakfast TV show, Harry said “I love my family” and that he was “grateful” to be able to spend around 45 minutes with Charles when he flew back to the UK.
Harry published his memoir Spare last year, in which he accused William of pushing him into a dog bowl in a row over the Duchess of Sussex.
It was also claimed William teased Harry about his panic attacks.
Further tensions between the royal brothers can be traced back to the early period of Harry’s relationship with wife Meghan, when his then fiancee had a falling out with the Princess of Wales in the run-up to their wedding.
Shortly before William spoke to the crowds at the Diana Award ceremony, the Duchess of Sussex returned to Instagram to launch a new business venture.
The social media teaser, posted to the new American Riviera Orchard Instagram account on Thursday, featured a vintage-style video of Meghan cooking and arranging white hydrangeas and roses.
The Diana Award was set up to promote the princess’s belief that young people have the power to change the world for the better.
Both William and Harry presented the inaugural legacy awards at St James’ Palace in 2017.