The Prince of Wales was joined by Leonardo DiCaprio as he viewed a fashion exhibition by designer Stella McCartney at Cop26.
Charles spoke with the Hollywood star, who has been a United Nations representative on climate change since 2014, at the Kelvingrove Art Gallery and Museum in Glasgow.
McCartney, the daughter of former Beatle Sir Paul, is known for her environmental activism and using vegetarian and animal-free alternatives in her work.
Pieces on display included mushroom-inspired hats, football boots, shoes and bags arranged amongst mossy outcrops.
Charles was pictured being given a tour of the installation by McCartney and speaking with Hollywood star DiCaprio upon arrival.
The Oscar-winning actor has attended several events and pop-ups during Cop26.
Earlier in the week, Kew Science, the research arm of Royal Botanic Gardens in Kew, said DiCaprio had passed through its Carbon Garden space, where scientists will be highlighting the role plants can play in providing solutions to climate change across Cop26.
DiCaprio, who describes himself as an actor and environmentalist on Instagram, updated his biography ahead of the event to include the hashtag #COP26.
He also added a link to the United Nations website page on climate change.
In 2016, the actor was an executive producer on The Ivory Game, which examined the ivory trade.
Oscar-winning director Fisher Stevens also filmed DiCaprio as he travelled around the world to see the effects of global warming for the 2016 feature Before The Flood.