World leaders have expressed that decriminalizing marijuana may assist in reducing drug-related violence.
"The global war on drugs has failed, with devastating consequences for individuals and societies around the world," the members of the Global Commission on Drug Policy say in a report.
"Fifty years after the initiation of the UN Single Convention on Narcotic Drugs, and 40 years after President (Richard) Nixon launched the US government's war on drugs, fundamental reforms in national and global drug control policies are urgently needed."
And saying that restrictions on marijuana should be loosened, the report urged governments to "end the criminalization, marginalization and stigmatization of people who use drugs but who do no harm to others."
The commission includes former Brazilian president Fernando Cardoso, former Colombian president Cesar Gaviria, Mexico's former president Ernesto Zedillo and the ex-UN chief Kofi Annan. It presents its report officially on Thursday in New York.
The group of prominent statesmen, many from countries on the frontline of the seemingly never-ending war on drugs, said purely punitive measures had in fact led to a situation where "the global scale of illegal drug markets -- largely controlled by organized crime -- has grown dramatically."
"Encourage experimentation by governments with models of legal regulation of drugs (especially cannabis) to undermine the power of organized crime and safeguard the health and security of their citizens," the report urged.
"Decriminalization initiatives do not result in significant increases in drug use," the report said, citing policies in Australia, Holland and Portugal.
Another priority, the report said, is to work on treatment. "Let's start by treating drug addiction as a health issue, reducing drug demand through proven educational initiatives and legally regulating rather than criminalizing cannabis," Cardoso said.