Pope Francis has requested to chew coca leaves during his forthcoming visit to Bolivia, according to Bolivian Culture Minister Marko Machicao.
Coca, the raw ingredient for cocaine, has been used in the Andes for thousands of years to combat altitude sickness and as a mild stimulant.
Mr Machicao said the government offered the Pope coca tea and the pontiff had "specifically requested" to chew coca.
The Vatican has not yet commented. The Pope travels to Bolivia on 8 July.
Coca leaves were declared an illegal substance under the 1961 UN convention on narcotic drugs.
But the growing of coca leaves for religious and medicinal purposes is legal and licensed in Bolivia.
Many indigenous Bolivians consider the coca bush a sacred plant and chewing its leaves or brewing them into a tea is very popular.
Bolivia's 2009 constitution even declared the coca leaf "a cultural patrimony".
President Evo Morales, who used to be a coca grower, has long campaigned to decriminalise the consumption of coca leaves.
If the Pope were to chew coca leaves during his visit to the Andean country it would provide strong backing for Mr Morales's campaign.
"We will be awaiting the Holy Father with the sacred coca leaf," Mr Machicao said.
The Pope's visit to Bolivia is part of a larger tour of Latin American countries which will also take him to Ecuador and Paraguay.