The Duke of Cambridge will give a speech tonight to mark the imminent start of an international conference that aims to tackle the threat to the world's endangered animals.
William will make an address at a Natural History Museum reception as world figures prepare to discuss ways of saving animals like elephants, rhinos and tigers tomorrow.
Charles will give a speech at the London Conference on the Illegal Wildlife Trade being hosted by the Government at Lancaster House during Thursday. William will also attend and it will be hosted by the Prime Minister.
A few days before the start of the anti-poaching summit the Duke and his brother Prince Harry reportedly went hunting in Spain for wild boar.
William has joined forces with the Prince of Wales to record a video message calling on the world to act now to save endangered animals.
The Prince and Duke have worked together before to raise the issue of animal conservation and William is royal patron of the wildlife conservation charity Tusk Trust, and last year formed the umbrella body United for Wildlife to help tackle the threat to the world's endangered species.
He said in the video: "This year, I have become even more devoted to protecting the resources of the Earth for not only my own son but also the other children of his generation to enjoy.
"I want them to be able to experience the same Africa that I did as a child."
During the day William will also attend a meeting of his United for Wildlife body at the the Zoological Society in London.