Pop star Pink has fired off a letter to Prince William after hearing how he allegedly killed an antelope during a hunting trip in Kenya.
Pink is a campaigner for an animal rights group
The US star wrote to the prince, saying she was "disgusted to learn that you kill animals for fun".
The singer was said to be on the prince's wish-list of performers at his 21st birthday party.
The prince has already denied spearing a dik-dik antelope with a Maasai warrior spear while in Kenya, although he does join fox hunts in the UK.
A spokesman for Prince William said he had received the letter and would be responding.
He said: "Prince William did not kill a small deer in Africa and anyone who writes to him, including Pink, will be reassured that it did not happen."
Pink, real name Alecia Moore, is an ardent supporter of the People's Campaign for Ethical Treatment of Animals (Peta), and often speaks out on animal rights issues.
In her letter to Prince William she wrote: "I was happy to hear that I was your first choice to play at your 21st birthday bash - then disgusted to learn that you hunt animals for fun and that you purposely rammed a spear through a tiny deer in Africa."
Leaving aside royal formalities she then went on to ask "Why? Was it some kind of 'trying to prove you're a man' trip?"
But she offered a hand of friendship by suggesting he telephone her for suggestions for alternative leisure activities.
She added: "We can all change and find more interesting things to do with your spare time than kill animals.
"Call me or Peta if you'd like any suggestions. Then maybe I'll come play at your next birthday..."