Prince William plans to participate in the United Nations climate conference in South America in the coming weeks, according to palace sources.
The father and son duo made a joint appearance on Thursday night at a event leading up to the environmental conference, which is set to be held in the Amazonian city of Belém.
The King and Prince were in attendance at the museum gathering, marking an unusual joint appearance at a climate summit preparatory event co-hosted by the United Kingdom administration.
King Charles has been a long-time champion of environmental conservation - and Prince William has assumed the responsibility, with his own climate innovation awards, which will be hosted in Rio ahead of the UN meeting.
Official representatives have described William's involvement at the next COP as assuming an significant responsibility in "environmental negotiations".
The monarch and his heir, arriving together in the official car, were introduced to guests including environmentalists, scientists, environmental activists, foreign representatives and government officials.
This participation included speaking in concert with President Emmanuel Macron of the French Republic and other world leaders at the Ocean Finance Summit in Monaco during the current year.
The climate conference will coincide with the the royal's sustainability recognition program, which will finish in the Brazilian city the eve of he participates in the climate conference on the sixth of November.
Last week the prince characterized the prize competitors as "contemporary champions".
The monarch has been a influential participant at earlier environmental conferences, giving the opening address in the United Arab Emirates for COP28, including the statement: "The Earth does not belong to us, we belong to the Earth".
"I have spent a significant amount of my life trying to alert people to the existential threats challenging our world over global warming, climate change and ecological decline," the sovereign addressed attendees.