Uruguay's move to legalise the production and sale of marijuana breaks international law, the world drugs body said Wednesday, warning it would encourage addiction.
"Uruguay is breaking the international conventions on drug control with the cannabis legislation approved by its congress," said the International Narcotics Control Board, a UN agency that oversees the implementation of international treaties on drugs.
INCB president Raymond Yans added he was "surprised" that Montevideo had "knowingly decided to break the universally agreed and internationally endorsed legal provisions of the treaty."
He accused the country's lawmakers of ignoring scientific evidence on the health risks of marijuana, and said claims the law would help reduce crime relied on "rather precarious and unsubstantiated assumptions."
The move "will not protect young people, but rather have the perverse effect of encouraging early experimentation, lowering the age of first use, and thus contributing to... earlier onset of addiction and other disorders," said Yans.
Uruguay's parliament voted on Tuesday to legalise marijuana, becoming the first nation in the world to oversee the production and sale of the drug.
"The war against drugs has failed," said Senator Roberto Conde as he presented the bill on behalf of the ruling leftist Broad Front, calling it an "unavoidable response" to that failure.
The law not only authorises the production, distribution and sale of cannabis, but also allows individuals to grow their own on a small scale, and creates consumer clubs -- all under state supervision and control.
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Oct 9, 2012
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Oct 4, 2012
The son of the former chairman of Mexico's Institutional Revolutionary Party is found dead. <em>Caption: In this Oct. 15, 2007, photo, Jose Eduardo Moreira Rodriguez poses for photographers in Saltillo, Mexico. (AP Photo/Alberto Puente)</em>
Sept 4, 2012
Mexico captures a leader of the country's Gulf Cartel, Mario Cardenas, alias "Fatso." <em>Caption: Mexican Navy officers flank Mario Cardenas Guillen, also known as "El Gordo" and "M-1," during his presentation to the media in Mexico City, Tuesday, Sept. 4, 2012. (AP Photo/Alexandre Meneghini)</em>
Aug 24, 2012
Mexican police shoot and wound two U.S. Embassy employees, whom sources later identify as CIA operatives, just south of Mexico City. <em>Caption: In this Aug. 24, 2012, file photo, an armored U.S. embassy vehicle is checked by military personal after it was attacked by unknown assailants on the highway leading to the city of Cuernavaca, near Tres Marias, Mexico. (AP Photo/Alexandre Meneghini, File)</em>
August 14, 2012
Armed men storm a bar in Monterrey, killing eight men in a hail of bullets, in an apparent dispute over drug dealing. <em>Caption: Police forensic investigation vehicles sit parked outside Matehuala Men's Club after a shooting inside the night club in Monterrey, Mexico, early Tuesday Aug. 14, 2012. (AP Photo)</em>
May 13, 2012
Suspected drug gang hitmen dumped 49 mutilated bodies, stuffed in bags, on a highway outside the northern industrial city of Monterrey. <em>Caption: Federal police stand guard on a vehicle behind a forensic truck containing bodies found on the highway connecting the northern Mexican metropolis of Monterrey to the U.S. border, along the Reynosa-Cadereyta road, in the town of San Juan near the city of Monterrey, Mexico, Sunday, May 13, 2012. (AP Photo/Christian Palma)</em>
May 4, 2012
The bodies of nine people were found hanging from a bridge and 14 others found dismembered in the city of Nuevo Laredo, just across the U.S. border from Laredo, in Texas. <em>Caption: Four of nine corpses are seen hanging from a bridge in the Mexican border city of Nuevo Laredo, Tamaulipas state, early morning on May 4, 2012. (RAUL LLAMAS/AFP/GettyImages)</em>
Feb 19, 2012
A fight between rival gangs at a prison just outside Monterrey in northern Mexico leaves 44 dead. <em>Caption: Araceli Guevara Ontiveros, the sister of Francisco Guevara Ontiveros --one of the 44 dead in a riot at The Apodaca prison-- is comforted while crying on his coffin during his wake in Monterrey, Nuevo Leon state, on February 21, 2012. (Julio Cesar Aguilar/AFP/Getty Images)</em>
Nov 24, 2011
More than 20 bodies are found in cars in Mexico's second city, Guadalajara, a day after the burned bodies of 16 people are found in the home state of the country's powerful drug lord, Joaquin "Shorty" Guzman. <em>Caption: A member of the forensic service carries one of the 26 corpses found this morning in three vehicles abandoned in Mexico's second most populous city of Guadalajara, Mexico, on November 24, 2011. (HECTOR GUERRERO/AFP/Getty Images)</em>
Oct 6, 2011
Mexican security forces find 32 bodies at several locations around Veracruz, just two days after the government unveiled a plan to bolster security in Veracruz state. <em>Caption: Mexican army soldiers walk towards their vehicle after seven bodies were found inside a vehicle in the Gulf port city of Veracruz, Mexico, late Friday Oct. 7, 2011. (AP Photo/Felix Marquez)</em>
Sept 20, 2011
Thirty-five bodies are found abandoned in two trucks on an underpass in the eastern Gulf city of Veracruz, which had been largely untouched by the violence. <em>Caption: Mexican marines stand guard in streets of Veracruz State, Mexico on 24 January 2012. (JOHAN ORDONEZ/AFP/Getty Images)</em>
Aug 25, 2011
Masked gunmen torch a casino in Monterrey, killing 52 people, most of them women. The attack takes less than three minutes. <em>Caption: Relatives of victims cry in front of the Casino Royale, in Monterrey, Mexico, on August 27, 2011. (Ronaldo Schemidt/AFP/Getty Images)</em>
Aug 20, 2011
Five headless bodies were found in Acapulco, taking the number of people killed in the popular Pacific resort to at least 25 in that one week. <em>Caption: Forensic personnel move the corpse of a person murdered in a hotel at the La Guinea neighbordhood in the town of Acapulco, Guerrero state, Mexico on August 24, 2011. (Pedro PARDO/AFP/Getty Images)</em>
Officials unearthed the first of what turned out to be more than 450 bodies buried in mass graves in the northern states of Durango and Tamaulipas. <em>Caption: Forensic personnel unload at the morgue bodies of people killed execution-style in Matamoros, Tamaulipas State, Mexico, on April, 11, 2011. (STR/AFP/Getty Images)</em>
Aug 25, 2010
Marines found the bodies of 58 men and 14 women at a ranch near the Gulf of Mexico in Tamaulipas state, 90 miles from the Texas border, after a firefight with drug hitmen in which three gunmen and a marine died. <em>Caption: A worker wearing protective suit and boots walks between two refrigerated trucks parked outside a funeral home where the bodies of 72 men and women that were allegedly killed by the Zetas drug gang, are kept in San Fernando, just 100 miles from the the Mexican border with the U.S. near the city of Matamoros, Thursday Aug. 26, 2010. (AP Photo/Guillermo Arias)</em>
July 24, 2010
Police unearthed 51 bodies in a grave outside Mexico's business capital, Monterrey, in northern Mexico over several days. Some corpses were burned beyond recognition. <em>Caption: View of the remains of two burnt bodies found in Monterrey, Nuevo Leon state, on October 20, 2010. The bodies were found under burnt wooden pallets. (Dario Leon/AFP/Getty Images)</em>
July 18, 2010
Gunmen burst into a birthday party in the northern city of Torreon, using automatic weapons to kill 17 party-goers and wound 18 others. Mexican authorities said later those responsible were incarcerated cartel hitmen let out of jail by corrupt officials. The killers allegedly borrowed weapons and vehicles from prison guards and later returned to their cells. <em>Caption: Police officers patrol a street in Torreon, in the Mexican northern state of Coahuila, Monday, July 19, 2010. (AP Photo/Ramon Sotomayor)</em>
June 28, 2010
Suspected cartel gunmen shot and killed a popular gubernatorial candidate in the northern state of Tamaulipas in the worst cartel attack on a politician to date. Rodolfo Torre, 46, and four aides from the opposition Institutional Revolutionary Party, or PRI, were ambushed on their way to a campaign event for the July 4 state election. <em>Caption: A billboard with the portrait of the candidate for Governor of Tamaulipas state for the Institutional Revolutionary Party (PRI), Rodolfo Torre, and reading 'A leader forever' is seen during his funeral at the Polyforum in Ciudad Victoria, Tamaulipas state, Mexico, on June 29, 2010. (LUIS ACOSTA/AFP/Getty Images)</em>
March 13, 2010
Hitmen killed three people linked to the U.S. Consulate in Ciudad Juarez in March, provoking "outrage" from U.S. President Barack Obama. <em>Caption:The U.S. national flag flutters at half-mast at the entrance of the consulate of the United States in Ciudad Juarez, Chihuahua state, Mexico on March 15, 2010. (Jesus Alcazar/AFP/Getty Images)</em>
Jan 31, 2010
Suspected cartel assailants killed 13 high school students and two adults at a party in Ciudad Juarez across from El Paso, Texas. <em>Caption: Students enter a high school in Ciudad Juarez, a city ridden by homicidal violence along Mexico's border with Texas. (Tim Johnson/MCT via Getty Images)</em>
Sept 15, 2008
Suspected members of the Zetas drug gang tossed grenades into a crowd celebrating Mexico's independence day in the western city of Morelia, killing eight people and wounding more than 100. <em>Caption: From left to right: Julio Cesar Mondragon Mendoza, Juan Carlos Castro Galeana, and Alfredo Rosas Elicea, are members of a group of hitmen called the 'Zetas' shown to the press at the General Attorney's office in Mexico City, on September 26, 2008. The three gangsters confessed that they are the authors of a grenade attack that killed eight people during the celebration of Independence Day in Morelia, western Mexico. (STR/AFP/Getty Images)</em>