Leonardo DiCaprio, Who Recently Teamed with Prince Harry, Meets Prince Charles

Owen Humphreys-WPA Pool/Getty Leonardo DiCaprio, Prince Charles and Stella McCartney

Prince Charles took part in a meeting of the minds with Hollywood and fashion royalty on Wednesday.

Queen Elizabeth's eldest son was spotted with Leonardo DiCaprio and Stella McCartney at the Kelvingrove Art Gallery and Museum in Scotland on day three of the COP26 United Nations Climate Change Conference. Prince Charles, 72, and DiCaprio, 46, have both been vocal environmentalists — in fact, the Oscar winner released a joint statement with Charles' son Prince Harry last month calling for an immediate suspension on oil and gas drilling in Africa's Okavango River Basin.

"Re:wild stands with the people of the Okavango River Basin, who depend on the health of the watershed for their survival," DiCaprio wrote on his Instagram page. "ReconAfrica is poised to pollute their farms and destroy a beautiful landscape—one that benefits all life on Earth—forever. Join us by signing the open letter at the link in bio. Together, we can #SaveTheOkavango. For all wildkind."

This isn't the first time Prince Charles and DiCaprio have crossed paths. Back in November 1997, the two met at the London premiere of Titanic — and the actor even introduced the prince to his mom, Irmelin Indenbirken.

John Stillwell/PA Images via Getty Leonardo DiCaprio and Prince Charles in 1997

Prince Charles also spent time on Wednesday with McCartney, who designed the halter dress Charles' daughter-in-law Meghan Markle wore to her wedding reception in May 2018. The daughter of Paul McCartney showed the royal around her sustainability-focused fashion installation at the climate change conference.

"This is the Decisive Decade and if we do not act decisively, we know the consequences," McCartney, 50, said in a statement. "A football pitch is disappearing from the Amazon every minute and 80% of that area is being used for animal agriculture."

She continued, "The future of fashion and our planet is vegan. I hope that by representing our industry and revealing my current material innovations at COP26, I can inspire action among private sector and government leaders by driving more nature-positive investments and incentives. To not collaborate now would be an injustice to future generations and to those already suffering the worst of climate change's effects. This is our chance and I do not believe in waste."

Earlier in the day, Prince Charles was shown a McLaren Racing Extreme E car, which races in remote corners of the world and across brutal terrains to raise climate awareness. He also met New Zealand native Emma Gilmour, the first female factory driver in the outfit's near 60-year history.

On Tuesday, Prince Charles delivered a speech at the World Leaders Action on Forest and Land Use event at the conference.

He called the meeting "absolutely vital" as "it is here that we will explore together the scale of the systemic shifts that need to happen really urgently if the world is to succeed in delivering a positive future for nature and people alike, and I mean urgently as so many people and communities are already suffering seriously from the increasingly dire impact of climate change. We also have to act before the hydrological cycle breaks down altogether."

Charles concluded by saying, "I can't believe how many times I've made speeches like this all over the world during the past 40 years and to no avail, but I can only pray that this session will provide us with a real sense of the seriously urgent, systemic shifts that need to happen to deliver on our vision, and I urge you all to take forward whatever we discuss today with implacable resolve and determination to make things happen on the ground."

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The climate change conference was has been attended by leaders and activists from around the world including U.K. Prime Minister Boris Johnson, Australian Prime Minister Scott Morrison, German Chancellor Angela Merkel and U.S. President Joe Biden, who met with Prince Charles on Tuesday.

And on Monday, the Prince of Wales was joined by wife Camilla, Duchess of Cornwall, son Prince William and daughter-in-law Kate Middleton at an evening reception where they watched Queen Elizabeth's address attendees in a personal message that paid tribute to her late husband Prince Philip's commitment to saving the planet. The monarch, 95, recorded the video message at Winsdor Castle last Friday after she "regretfully" decided not to attend the summit as scheduled due to recent health issues.