Jay Z has slammed the war on drugs as an "epic fail".

In the video, which runs for nearly four minutes and features illustrations from artist Molly Crabapple, Jay said: "Drugs were bad; fried your brain. And drug dealers were monsters, the sole reason neighbourhoods and major cities were failing.

"No one wanted to talk about Reaganomics and the ending of social safety nets, the defunding of schools and the loss of jobs in cities across America. Young men like me who hustled became the sole villain, and drug addicts lacked moral fortitude."

The 45-year-old star - who has four-year-old daughter Blue Ivy with wife Beyonce - insisted more black people were imprisoned than their white counterparts as he discussed the mandatory minimum sentencing that put low-level drug dealers in jail, New York's tough Rockefeller laws and the "problem" of deadly narcotic crack.

He said: "Even though white people used and sold crack more than black people, somehow it was black people who went to prison.

"Crack is still talked about as a black problem."

Further claiming double standards, Jay slammed the hypocrisy of "the NYPD [raiding] our Brooklyn neighbourhoods, while Manhattan bankers openly used coke with impunity" and objecting that there are "kids at dorms in Columbia, where rates of marijuana use are equal to or worse than those in the hood, [who] are never targeted or ticketed."

The rap mogul - whose real name is Shawn Carter - concluded the US' tough stance has failed as drug usage rates are as high as they were when the laws were implemented and urged for a rethink on the policies. He said: "Rates of drug use are as high as they were when Nixon dec lared this so-called war in 1971. "Forty-five years later, it's time to rethink our policies and laws. The War on Drugs is an epic fail."