“I’ve been involved in many charities for most of my life and I get a huge amount of fulfillment giving back to as many people as possible,” he told the crowd on Wednesday.

“My life is charity, always has been, always will be.”

He also said he had enjoyed “the most incredible Kobe steak, both for dinner last night and lunch today”, adding: “Your warmth, your compassion, your generosity, every single element of the Japanese culture is really unique and very, very special.”

The summit was hosted to help promote the importance of sports in bringing people together and raising awareness about special causes and was attended by several international high-profile representatives, such as former All Black rugby player Dan Carter and the Royal Australian Navy veteran and Invictus gold medallist Steve James.

The 38-year-old will then travel to Singapore later this week for his fundraising Sentebale Polo Cup this weekend, which he has said will help young people affected by HIV/Aids.

Speaking about the annual event last week, the Duke said: “The annual Polo Cup is essential to Sentebale’s vital work ensuring children and young people are healthy, resilient, and able to thrive.

“The funds raised this year will support our Clubs and Camps programme, which provides intensive psychosocial support to young people living with HIV.”

The Duke will play on the Royal Salute Sentebale Team, against the Singapore Polo Club Team, which will be captained by the charity’s ambassador and his long-time friend, Mr Figueras.