LIMA, Peru – Peru’s coca crop grew for a fourth straight year, edging the country closer to its South American neighbor Colombia in overall cultivation of the raw material of cocaine, the United Nations said Tuesday.

Owing to a 16 percent drop in acreage in Colombia, overall coca cultivation fell 5.3 percent in the world’s three major coca-producing nations last year, the U.N. Office of Drugs and Crime said.

Coca cultivation increased just 1 percent in Bolivia, the No. 3 producer, compared to a 6.8 percent rise in Peru, the U.N. said in its annual report on the crop.

That put the overall area under coca cultivation at 231 square miles in Peru against 263 square miles for Colombia and 119 square miles for Bolivia. The U.N. figures are based on satellite images and field visits.

The size of Peru’s coca crop has nearly doubled in the past decade, and the head of the country’s anti-drug agency, Romulo Pizarro, acknowledged “a sense of frustration” at the steady rise despite manual eradication and alternative development.

“Drug traffickers don’t sit by with their arms crossed,” he said. “Worldwide demand has increased.”

The head of the U.N. drug office in Colombia, Aldo Lale-Demoz, said Tuesday that the decrease in Colombia’s drug crop argues for “transferring, repeating and multiplying” eradication efforts to other countries.

But critics of Washington’s more-than-30-year war on drugs say the latest U.N. numbers instead support their argument that an emphasis on eradication has failed to reduce supply at the cost of billions of dollars.