Uruguay's Senate is expected to pass a law on Tuesday making the small South American nation the world's first to allow its citizens to grow, buy and smoke marijuana.
The pioneering government-sponsored bill establishes state regulation of the cultivation, distribution and consumption of marijuana and is aimed at wresting the business from criminals.
Cannabis consumers would be allowed to buy a maximum of 40 grams (1.4 ounces) each month from state-regulated pharmacies as long as they are over the age of 18 and registered on a government data base that will monitor their monthly purchases.
Uruguayans would also be allowed to grow up to six plants of marijuana in their homes a year, or as much as 480 grams (about 17 ounces). They could also set up smoking clubs of 15 to 45 members that could grow up to 99 plants per year.
Uruguay's attempt to undo drug trafficking is being followed closely in Latin America where the legalization of some narcotics is being increasingly seen by regional leaders as a possible way to end the violence spawned by the cocaine trade.
Rich countries debating legalization of pot are also watching the bill, which philanthropist George Soros has supported as an "experiment" that could provide an alternative to the failed U.S.-led policies of a long "war on drugs".
The bill, which passed the lower chamber of Congress in July, gives authorities 120 days to set up a drug control board that will regulate cultivation standards, fix the price and monitor consumption.
The use of marijuana is legal in Uruguay, one of the most liberal Latin American countries, but cultivation and sale of the drug are not.
Other countries have decriminalized marijuana possession and the Netherlands allows its sale in a coffee shop system, but Uruguay will be the first nation to legalize the whole chain from growing the plant to buying and selling its leaves.
Several countries such as Canada, the Netherlands and Israel have legal programs for the growth of medical cannabis, but do not allow cultivation of marijuana for recreational use.
Last year, the U.S. states of Colorado and Washington passed ballot initiatives that legalize and regulate the recreational use of marijuana.
Uruguay's leftist President Jose Mujica defends his initiative as a bid to regulate and tax a market that already exists but is run by criminals.
"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 of society," the 78-year-old former guerrilla fighter told Argentine news agency Telam.