A ban on sales of loose cigarettes and tobacco advertising went into effect Thursday in Colombia, the health ministry said.
The clampdown is part of an anti-tobacco law approved by Congress in June 2009, following a ban on smoking in enclosed public places in May 2008.
Cigarettes can now only be sold in packets of 10 or more and tobacco companies are no longer allowed to advertise, including on foreign TV channels broadcasting in the country.
All cigarette packets must also carry health warnings.
At least five million adults out of a population of some 46 million are regular smokers in Colombia, according to official estimates.
Some 25,000 people die each year from one or some of the 15 types of cancer linked to cigarette smoking, anti-tobacco law supporter Senator Dilian Francisca Toro told Caracol radio.
Last May, the multi-national group British American Tobacco acquired Protabaco, the second largest cigarette company in Colombia, for $452 million.