On Tuesday, Uruguay was one step closer to becoming the first country to legalize the growing, sale and smoking of marijuana. The progressive new law hopes to curb drug trafficking in the small South American country, however, some say it may not be legal in the eyes of the international community.

The new bill, which was approved by 16-13 votes in the Uruguayan Senate, allows marijuana consumers to buy a maximum of 40 grams (1.4 ounces) a month from licensed pharmacies with a set of restrictions. Consumers must be Uruguayan residents over the age of 18 and they must be registered on a government database that monitors their monthly purchases, Voice of America reported.

Registered users will be able to start buying over the counter marijuana in April.

Uruguayans will also be allowed to grow six cannabis plants in their homes a year, or up to 480 grams (about 17 ounces) after the law is implemented in 120 days. Smoking clubs consisting of 15 to 45 members that can grow up to 99 plants a year will also become legal.

The government will have the next 120 days to set up a drug control board that will oversee standards for cultivation, monitor consumer consumption and set marijuana prices.

Uruguayan President Jose Mujica defended the new law as a new way to deal with the drug trafficking world. “We’ve given this market as a gift to the drug traffickers and that is more destructive socially than the drug itself, because it rots the whole society,” the leftist president told Argentina’s Telam.

While some around the world see Uruguay’s new marijuana law as an experimental move against the failed “war on drugs,” others are doubting its legality. According to the BBC, the International Narcotics Control Board (INCB), a UN drugs watchdog, says Uruguay’s decision to legalize the production, sale and consumption of marijuana violates international law.

In a statement released on Wednesday, INCB President Raymond Yans said he was “surprised that a legislative body that endorsed an international law and agreements...knowingly decided to break the universally agreed and internationally endorsed legal provisions of the treaty.”

Yans added, “The decision of the Uruguayan legislature fails to consider its negative impacts on health since scientific studies confirm that cannabis is an addictive substance with serious consequences for people’s health. In particular, the use and abuse of cannabis by young people can seriously affect their development.”

Once President Mujica signs the new bill into law, Uruguay will officially become the first and only country to legalize the whole spectrum of growing, selling and consuming marijuana. Several Latin American countries with large drug trafficking issues will look at Uruguay to seek how successful it is at combating illegal drug trade. Countries that are also debating the legalization of marijuana will also keep a close eye on Uruguay and the bill’s success.

Only a few countries have decriminalized the possession of marijuana, while several have legal programs that allow for the growth of medical marijuana.