Queen Latifah said racism is "still alive and kicking" as she addressed the crowd at VH1´s Hip Hop Honours awards.
The rapper was speaking in the wake of protests across the US following the killing of two black men by police last week, as well as the fall-out after five police officers were killed when a man opened fire at a peaceful protest in Dallas.
Latifah, who was honoured at the ceremony, said: "Listen, we all know our world is really tense right now. It's a lot of tension, it's a lot of angst, it's a lot of hurt, a lot of pain.
"I'm hoping that we can somehow manage to channel all of these emotions that we have in a positive way, and really do something to change our world."
Footage from the event, which focused on female artists in hip-hop, showed her telling the crowd her wealth compared to fellow musicians including P Diddy and Missy Elliott did not matter.
"I don't care how much or things I have, or Puff has, or Missy has," Latifah said.
"If I go outside and try to hail a cab and he passes me for the white woman standing right there, that racism is still alive and kicking. And we have to change that."
Latifah added: "I'm not blaming the white lady, she needed a cab too. I'm just saying we need to change this attitude and we must demand respect as women."