BOGOTA, Colombia (AP) – A key component of the U.S.-backed war on drugs appears to be failing.

Despite record drug seizures and spraying of herbicides, production of the plant used to make cocaine increased by 8 percent in Colombia, to 330 square miles, the United Nations said Tuesday – even as authorities sprayed coca fields totaling 25 times the size of Manhattan. The findings come on the heels of a similar report in April by the U.S. Office of National Drug Control Policy, which showed Colombia’s coca production skyrocketed 26 percent from 2004 to 2005, in part due to a near-doubling of the area surveyed.

The two reports are the strongest evidence yet that a cornerstone of the U.S.-led war on drugs – the aerial fumigation of coca fields – is failing to meet its goal of halving coca production in the Andes.

The results may hamper efforts by President Alvaro Uribe to win additional U.S. backing for the anti-drug strategy that has cost American taxpayers $4 billion since 2000.

The report said Colombian coca production expanded for the first time in five years, by 23 square miles.

“If this is the start of a return to much higher levels of coca, then it will be a problem,” the U.N. agency’s executive director Antonio Maria Costa told a news conference in Bogota.

“But I don’t think that will happen. The government has every intention to continue its eradication efforts at the same high level as the past few years.”

Partially offsetting the rise in Colombian production were declines in the world’s two other coca-producing countries, Bolivia and Peru.

Overall, coca production in the Andean region rose 1 percent, to 616 square miles from 2004, according to the U.N.’s Andean coca survey.

In Colombia, the world’s largest cocaine producer, the biggest increases were in the lawless, largely uninhabited jungles near its borders with Venezuela and Ecuador.

The spread of the coca frontier eastward toward Venezuela is in line with comments by U.S. anti-drug officials who have alleged that corruption within the government of Venezuelan President Hugo Chavez may be converting Colombia’s neighbor into a major drug route.

Colombia is believed to be the source of 90 percent of the cocaine consumed in the United States.

Last year, the government eradicated a record 656 square miles of coca, mainly through aerial spraying of the herbicide glyphosate, up from 529 square miles in 2004.

But with drug traffickers developing techniques to better camouflage illegal crops and increase yields, Uribe has asked the Bush administration to boost financing for fumigation efforts.

However, key members of the U.S. Congress and growing numbers of Colombians have suggested it may be time to give up the potentially environmentally harmful practice in favor of alternative economic programs for the poor farmers who grow coca on behalf of the country’s cartels.

Currently about a third of the roughly $700 million in annual U.S. aid to Colombia funds economic and social development programs.

Although production is on the rise in Colombia, the U.N. said it declined in Peru and Bolivia.

Coca production in Bolivia fell by 8 percent last year, according to the U.N. The United States, however, is concerned Bolivia’s leftist, coca-growing President Evo Morales – who took office in January – could relax his country’s drug-fighting efforts.

In Peru, the world’s second-largest cocaine producer, the coca crop declined by 4 percent.

The apparent declines differ widely from findings by the United States, based more heavily on satellite imagery, which estimated coca plantings grew by 38 percent in Peru and nearly 10 percent in Bolivia last year.

For anti-drug efforts to be successful, Costa said the United States and Europe must curb cocaine consumption and support alternative crop development programs in South America.

“Our aid efforts need to be multiplied at least tenfold in order to reach all impoverished farmers who need support,” he said in a statement.

Only subscribers are eligible to post comments. Please subscribe or to participate in the conversation. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.