A growing number of Latin American countries are debating whether or not to legalise the use and sale of marijuana.

For the first time, the former presidents of Mexico, Brazil and Colombia are discussing the legalisation as a means of curbing narcotics-related violence from rival cartels, which thrive off the illegal trade.

The talks are part of a debate spreading throughout the region in which some say the militarised war on drugs has failed and that it is time for a new alternative.

Al Jazeera's Lucia Newman reports from Buenos Aires, Argentina's capital.