Bolivia has informed the United Nations it is renouncing the world body's anti-drug convention because it classifies the coca leaf as an illegal narcotic.
Bolivia's decision comes after a proposal by president Evo Morales to remove language that obliges countries that have signed the convention to ban coca-leaf chewing was rejected following US objections.
Bolivia contends the coca leaf in its natural form is not a narcotic and forms a part of Andean culture.
The Foreign Ministry confirmed that Bolivia's decision was presented to UN Secretary-General Ban Ki-moon in New York.
Bolivia plans to rejoin to the 1961 Single Convention on Narcotic Drugs later, but noting its objection to the penalisation of coca chewing.