The Prince of Wales is scheduled to attend the COP30 climate summit in South America during November, as confirmed by palace sources.
The father and son duo made a joint appearance on Thursday evening at a gathering preceding the environmental conference, which is scheduled to take place in the northern Brazilian city of Belem.
The King and Prince were present at the museum gathering, marking an noteworthy combined presence at a environmental conference preliminary meeting organized in partnership with the United Kingdom administration.
King Charles has been a long-time champion of protecting nature - and the Prince of Wales has taken on the baton, with his own environmental prize initiative, which will be hosted in Rio before the climate conference.
Official representatives have described Prince William's attendance at the upcoming climate summit as taking on an crucial position in "environmental negotiations".
The King and Prince of Wales, making a joint entrance in the royal vehicle, were introduced to attendees such as environmentalists, scientists, environmental activists, foreign representatives and politicians.
This participation featured addresses together with French leader Macron of France and other world leaders at the Marine Economy Conference in the Principality of Monaco in recent months.
The COP30 summit will align with the the royal's Earthshot environmental awards, which will wrap up in the Brazilian city the day before he participates in the climate conference on 6 November.
Recently the William characterized the Earthshot finalists as "contemporary champions".
King Charles has been a key figure at previous climate summits, giving the opening address in the United Arab Emirates for COP28, including the reminder: "The Earth does not belong to us, we belong to the Earth".
"Throughout my life I've dedicated a significant amount of my life trying to raise awareness about the existential threats confronting humanity over climate change, global temperature increases and species extinction," the King told delegates.