Peru has regained its traditional role as the world's leading producer of coca leaf, the raw material for cocaine, according to the United Nations Office on Drugs and Crime (UNODC). UNODC noted the shift in its World Drug Report 2010, released this week.

[inline:global-coca-growing-un-2010.jpg align=left caption="UN breakdown of coca growing by nation, with total. Note that the drop in cultivation beginning in 2001 coincides with the introduction of high-yield coca seeds, and so does not necessarily reflect production levels."]Peru now accounts for 45% of the global coca crop, compared to 39% for Colombia and 15% for Bolivia. This marks the first time since 1997 that Peru has eclipsed Colombia as the world's largest producer. Unlike Peru and Bolivia, Colombia had not traditionally been a coca producer, but that changed in the 1980s as Colombian drug trafficking groups began encouraging the planting of the crop at home.

UNODC cited a steady decline in production in Colombia over the past few years for the shift and argued that it showed the Colombian government's US-backed anti-drug policies were working. Coca cultivation declined by 16% in Colombia last year, according to the UNODC, marking a decline of 58% since production peaked a decade ago.

"The drug control policies adopted by the Colombian government over the past few years -- combining security and development -- are paying off," said UNODC executive director Antonio Maria Costa.

The Colombian government, too, joined in lauding itself. "This success is thanks to the democratic security policy and its integral approach to the fight against drugs, including manual eradication and aerial spraying of coca crops," it said in a statement. "The sustained efforts of the Colombian authorities have led to a significant reduction in the global supply of cocaine," it added.

Not so fast, buckaroo. Global cocaine production was down only an estimated 5%, according to the UNODC. And, it noted: "It appears that, despite radical changes within countries, total cocaine output has been fairly stable over the last decade."

And in a classic example of the balloon effect, the decline in coca and cocaine production in Columbia has been matched by steady increases in Peru. Coca cultivation there has increased by 55% over the past decade, UNODC said. Coca production in Bolivia has been relatively stable, the report found.

Dr. Arlene Tickner of the University of the Andes in Bogota told the BBC that, rather than being a success, Plan Colombia had only pushed production beyond Colombia's borders. "As a drug policy, I think it has been a relative failure," she said. "If we look at the Andean region as a whole what we see is not only that coca crops are basically the same size as the year 2000 but also that the potential cocaine production from those crops is the same as well."

The Peruvian government took issue with the UNODC, with Foreign Minister Jose Garcia Belaunde telling reporters Wednesday that UNODC figures did not jibe with either US DEA or Peruvian estimates. That is true, but the UNODC is comparing its figures to previous UNODC figures, not those of the DEA or the Peruvians.