"We all have a responsibility to create an environment where such abuse is not tolerated, and those who choose to spread hate and division are held accountable for their actions.
"That responsibility extends to the platforms where so much of this activity now takes place.
"I commend all those players, supporters, clubs and organisations who continue to call out and condemn this abuse in the strongest terms. - W"
While some royal fans were pleased with Will's message, one writing, "Well said. Thank you William", others were not at all impressed with the Prince's "hypocrisy".
"Where was this energy for Meghan when she was getting it constantly?" wrote one user.
Indeed, many fans were outraged that William had waited until now to speak out against racism, when his own sister-in-law, Meghan Markle, has been a victim of incessant online attacks due to the colour of her skin without the royal saying a word in her defence.
A popular Meghan Markle and Prince Harry fan page on Instagram, with more than 280,000 followers, took to the platform to voice their upset. A post which was met with a fanfare of support from their followers.
"I find it very, very sad how people put everything material above their own family's well-being. I find it incredibly sad how a person actually uses everything for marketing purposes instead of standing behind their own family."
"I believed in William until now, and wish the brothers come back together in harmony. But guys, what William pulled off today actually makes my skin crawl.
"Meghan has been publicly racist, attacked, bullied, persecuted, lied to by the palace for months... and William has never put his finger to the keyboard to stand behind his brother and sister-in-law!
"Now he comes along and personally puts out a cheap anti-racism ad!... But how about - to come across more authentically - standing behind your own family?!
"I've just unfollowed the BRITISH Royal Family, I can't take this hypocrisy anymore."
Fans were quick to agree with the popular account, one writing, "The Royal Family are never going to change and will continue to be performative...it continues to show.
"The fact that they STILL have not come out to say anything in support of the Harry and Meghan 🙄🙄."
Another added to the conversation, commenting, "You'e not alone. I’ve stopped reading any of their posts. Want nothing to do with that Family Firm. 💔what They have done is evil. And absolutely shameful."