The Duke of Sussex has paid tribute to his late mother, Diana, Princess of Wales, for "living by truth and service to others" as he prepares to mark what would have been her 60th birthday.

Prince Harry, 36, told winners of this year’s Diana Award, that she believed young people had "the power to change the world".

In a video message, he described how he would join his brother, the Duke of Cambridge, 39, at the unveiling of a statue of the late Princess at Kensington Palace on Thursday.

"Later this week, my brother and I are recognising what would have been our mum’s 60th birthday,” he said. "And she would be so proud of you all for living an authentic life with purpose and with compassion for others.”

He added: "Never be afraid to do what’s right. Stand up for what you believe in and trust that when you live by truth and in service to others, people will see that, just as they did with my mum."

The Duke’s comments are the first he has made in public about the statue unveiling.

Having flown to London from California this weekend, he is currently isolating at Frogmore Cottage, Windsor.

He is expected to view the bronze sculpture privately, allowing himself a moment of reflection away from the cameras ahead of the brief ceremony, which will be attended only by close family, members of the statue committee, sculptor Ian Rank-Broadley and garden designer Pip Morrison.

The statue was installed in the Palace’s sunken garden this weekend but remains hidden from public view by a large wooden container. It is said to portray the Princess at her "youthful best", although the specific details have been shrouded in secrecy.

The Diana Award, the only charity bearing the Princess’s name, honours young people who work to improve the lives of others.

The Duke told this year’s recipients at a virtual ceremony: "Our mum believed that young people have the power to change the world. 

"She believed in your strength because she saw it day in and day out. And in the faces of young people exactly like you, she witnessed a boundless enthusiasm and passion and I too see those same values shine through."

He added: "Meg and I fundamentally believe that our world is at the cusp of change, real change for the good of all. But the question before us is what that change will look like.

"There is great need for young leadership and there is no greater time to be a young leader. I believe in you. We believe in you.

"You are putting the ‘dos’ behind the ‘says’ and this is the personification of our mother’s legacy."

The Duke said he hoped this year’s awards would inspire people to "be part of a future where humanity is cherished", where communities were supported and where people were considerate and compassionate to each other, "both online and off".

Since moving abroad, the Duke has repeatedly extolled the virtues of living "authentically" and "truthfully".

When the Queen confirmed earlier this year that the Duke and Duchess would not "continue with the responsibilities and duties that come with a life of public service,” the couple appeared to hit back by insisting "service is universal".

Prince Harry has spoken of his mother many times in recent interviews, telling Oprah Winfrey on their Apple TV+ series that he had no doubt she would be proud of him, adding: "I’m living the life she wanted to live for herself. I’m living the life that she wanted us to be able to live.

"So not only do I know that she’s incredibly proud of me but that she’s helped me get here. I’ve never felt her presence more as I have done over the last year."