The godfather of modern hip-hop has decided enough is enough. Russell Simmons, the co-founder of Def Jam records and the inspiration behind bands as diverse as Run-DMC, the Beastie Boys and LL Cool J, is as sick of the lazy vulgarity of rap music as many of the rest of us.

Yesterday, he called for a voluntary ban on the three words he considers the most unacceptable, and among the most common, describing "bitch", "ho" and "nigger" as "extreme curse words" that were inconsistent with any sense of social responsibility by rap artists or their record companies.

"The words 'bitch' and 'ho' are utterly derogatory and disrespectful of the painful, hurtful, misogyny that, in particular, African American women have experienced in the United States," Simmons' organisation, the Hip-Hop Summit Action Network, said in a statement.

"The word 'nigger' is a racially derogatory term that disrespects the pain, suffering, history of racial oppression and multiple forms of racism against African Americans and other people of colour," it added.

CNN is focusing on this today.