It's the largest producer of cocaine in the world and a key supplier of heroin to the United States. According to the CIA, Colombia produces 535 metric tons of cocaine a year, most of it for the U.S. market. The South American country has retained its status as key cocaine producer in spite of an ambitious anti-drug agreement launched a decade ago with the financial support of the United States. The agreement is called Plan Colombia. Since 2000, the plan has cost the United States $7 billion, according to the Inter-American Dialogue, a Washington think tank that has closely monitored the implementation of Plan Colombia. The money has been mostly used to help Colombia strengthen its police and military. Before the implementation of Plan Colombia, 50 % of the Colombian territory did n't have a government security presence. Marta Lucia Ramirez, a former Colombian minister of defense and one of the architects of Plan Colombia, says the agreement has helped her country to strengthen democracy and government institutions. It has also increased the Colombian government's ability to fight what she calls narco-terrorism. But Ramirez also says that the high drug demand in the U.S. makes it difficult to eradicate production at home. I really believe that the American strategy against drugs is not enough. It's probably a failure. It's -LSB- a policy -RSB- that they have to review, says