The Prince of Wales is scheduled to attend the United Nations climate conference in Brazil next month, as confirmed by royal officials.
The father and son duo made a joint appearance on Thursday night at a event preceding the climate summit, which is set to be held in the Amazonian city of Belém.
The royal pair were present at the museum gathering, marking an noteworthy combined presence at a pre-COP30 gathering co-hosted by the British authorities.
The King has been a consistent supporter of protecting nature - and the Prince of Wales has assumed the responsibility, with his own environmental prize initiative, which will be taking place in South America before the COP summit.
Palace insiders have described Prince William's attendance at the upcoming climate summit as assuming an important role in "environmental negotiations".
The King and Prince of Wales, arriving together in the royal vehicle, were welcomed participants featuring environmentalists, researchers, climate change campaigners, foreign representatives and politicians.
This involvement included speaking together with President Emmanuel Macron of France and other world leaders at the Blue Economy and Finance Forum in Monaco during the current year.
The climate conference will align with the the royal's sustainability recognition program, which will wrap up in the Brazilian city the eve of he participates in the COP summit on the sixth of November.
Last week the William characterized the Earthshot finalists as "modern-day pioneers".
King Charles has been a key figure at earlier environmental conferences, providing the introductory remarks in Dubai for COP28, including the observation: "We are custodians of the planet, not its owners".
"I have spent a significant amount of my life trying to warn of the survival risks challenging our world over climate change, environmental shifts and biodiversity loss," the King told participants.
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