Prince William gets tough question as he and Robert Irwin team up for conservation hike in South Africa ahead of Earthshot Prize

Prince William and Robert Irwin have collaborated on a selfie video for their joint 23 million Instagram followers after undertaking a hike together in South Africa this week.

The duo were in Cape Town ahead of attending the annual Earthshot Prize Awards on Wednesday night (local time), an initiative founded by the Prince of Wales, for which the 20-year-old Irwin acts as an ambassador.

WATCH THE VIDEO ABOVE: Robert Irwin and Prince William share a message from South Africa.

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On Tuesday they embarked upon a walk up to Signal Hill, famous for its views of the city and nearby Table Mountain, the BBC reported.

Signal Hill is in the Unesco World Heritage-listed Cape Flora Region, which is renowned for its biodiversity.

“G’day, it’s Robert here, with, of course, Prince William,” Irwin says in the video.

“Lovely to see you. How are you enjoying South Africa so far?”

The prince, 42, responds: “Good thanks, really good, having a lovely time so far, loving it.”

Robert Irwin puts Prince William on the spot with ‘tough question’ while visiting Cape Town. Credit: robertirwinphotography/Instagram

“Robert, you’ve been a fantastic ambassador for us at the moment, so looking forward to the prize on Wednesday – tune in!”

Irwin then quizzes William on his favourite African animal, which the prince thought was a “really tough question”.

“My children ask me this regularly. I think it’s going to have to be the cheetah,” William says.

“Cheetahs, OK. Very cool,” Irwin says.

”It’s chameleons for me, the unsung hero, I love them.

“Thanks so much for having me, for having us, Earthshot Week has been amazing so far and I cannot wait for tomorrow night. South Africa rules!”

The video was shared across both Irwin’s and the Prince and Princess of Wales’ Instagram pages.

Prince William, Prince of Wales talks to Robert Irwin during his visit at Signal Hill on Tuesday. Credit: Chris Jackson/Getty Images

“A wonderful morning for a hike on the stunning Signal Hill, Cape Town, discussing the amazing conservation work happening here! I’m honoured to be part of the @Earthshotprize family, and can’t wait for the Awards tomorrow night,” Irwin’s caption read.

Fans were quick to react, dubbing Irwin the “Prince of Australia”.

“The Prince of England and the Prince of Australia in one shot,” one said.

“Great to see Aussie and English royalty together,” another added.

“Two royal advocates for Mother Earth in one view, amazing!” a third said.

Prince William and Robert Irwin meet with youth conservation volunteers in Cape Town. Credit: Getty

The hike up Table Mountain took place on the second day of William’s four-day trip to Africa and the pair met with local park rangers, mountain rescue volunteers, biodiversity experts and firefighters during the outing.

“Prince William, myself and everyone here have certainly fallen in love with Cape Town,” Irwin told a group of media outlets after the walk, as per Daily Mail.

“It’s a beautiful location and the conservation work is being done here, it just fills my heart with hope.”

“I really loved having a conversation with Prince William about the importance of support for rangers.

“They are on the front line of conservation and you have to remember that these days conservation can be a dangerous business,” the wildlife warrior went on.

“And it’s really nice to know that Prince William is ensuring rangers are valued and they get the resources and the support they need. Very encouraging steps in the right direction.

“It’s great that William is putting himself behind this. Protecting the environment is about protecting people too.”