The Duke of Cambridge has expressed his concerns for his children's generation after an experience at school left his son, Prince George, feeling "confused".
Exclusive: Queen Rania of Jordan 'humbled' to be part of Prince William's visionary Earthshot Prize
During an interview with BBC Newscast on BBC Sounds ahead of his inaugural Earthshot Prize, the doting father opened up about his eight-year-old son's litter picking outing, which was organised by Thomas's Battersea.
WATCH: Prince William reveals concerns for Prince George's generation
Prince William, 39, admitted he is worried that his son's generation might still be talking about climate change in 30 years' time, when it "will be too late".
MORE: Prince William says 'there’s no time to waste' in climate change battle
READ: Prince William wants to help tackle climate change so he can 'look his children in the eye'
"So George at school recently has been doing litter picking and I didn't realise but talking to him the other day he was already showing that he was getting a bit confused," he explained.
"[He was] a bit sort of annoyed by the fact they went out litter picking one day and then the very next day, they did the same route, same time and pretty much all the same litter they picked up was back again.
Prince George is a pupil at Thomas's Battersea
"And I think that for him he was trying to understand how and where it all came from. He couldn't understand, he's like, 'Well, we cleaned this. Why has it not gone away?'"
He also told presenter Adam Fleming: "It shouldn't be that there's a third generation now coming along having to ramp it up even more.
"And you know, for me, it would be an absolute disaster if George is sat here talking to you or your successor, Adam, you know in like 30 years’ time, whatever, still saying the same thing because by then we will be too late."
Prince William added that his father Prince Charles, who is known for his long-standing commitment to green issues, had a "really rough ride" when he first started talking about climate change.
Of his father, William remarked: "It's been a hard road for him. My grandfather started off helping out WWF a long time ago with its nature work and biodiversity, and I think that my father’s sort of progressed that on and talked about climate change a lot more, very early on, before anyone else thought it was a topic.
Prince William has admitted he is worried about his son's generation
"So yes, he's had a really rough ride on that, and I think you know he's been proven to being well ahead of the curve."
He added that his viewpoint had changed since he had his own children, saying: "I want the things that I've enjoyed – the outdoor life, nature, the environment - I want that to be there for my children, and not just my children but everyone else's children.
"If we're not careful we’re robbing from our children's future through what we do now. And I think that's not fair."
BBC Newscast: the Prince William interview airs on 14 October. The Earthshot Prize Awards Ceremony will be broadcast on BBC One at 8pm BST on 17 October.
Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.