Tackling the "pernicious" illegal trade in wildlife will be a "key test" of the ability of nations to confront any global challenge, the Duke of Cambridge has said.
William, who has been campaigning in recent years for an end to the slaughter of endangered spices for their horns, skins or tusks, said the issue was a crisis that needed a "coalition of politicians and business leaders".
The Duke set up his umbrella group United for Wildlife in 2013 to try to find a solution to the problem he has raised in separate meetings with US president Barack Obama and his Chinese counterpart Xi Jinping earlier this year.
Writing an opinion piece for the Financial Times, under the heading "The illegal wildlife trade is the elephant in the room," the second-in-line to the throne said: "We must also make clear that tackling the pernicious illegal trade in wildlife is a key test of our communal ability to confront any global challenge.
"If we do not tackle it in a concerted way, the result will not just be the extinction of some of the world's iconic animals. If we let these animals vanish on our watch, the impact on our collective confidence to tackle any other global issue will be devastating."
The Duke also described how about 80% of Africa's tourist revenue is generated from visitors watching wild animals, many of them threatened by poachers.
William is due to record a speech this month which will be broadcast at a later date on the Chinese terrestrial channel CCTV1, as part of a series of programmes called Let's Talk.
A Kensington Palace spokesman has said: "The Duke is grateful to have this opportunity to explain how people around the world must work together to save some of the planet's most critically endangered species before they are lost forever."
The Duke joined forces with former England footballer David Beckham and ex-basketball star Yao Ming last year to record a video message urging people around the world not to support the trade in rhino horn.
William ended his piece with a positive rallying cry: "In national capitals, in corporate boardrooms and on the ground momentum is building. This is a battle we can win. And given the importance of this issue to our global collective confidence, we really cannot afford to fail."