Revenue from opium production in Afghanistan soared by 133 percent last year to about $1.4 billion, or about one-tenth of the country's GDP, according to a United Nations report received Friday.
The U.N. Office on Drugs and Crime said the price rise was due to a plant disease that wiped out much of the opium crop in 2010. Although yields returned to pre-blight levels in 2011, the prices have remained high, the survey said.
Definitive statistics are hard to obtain in Afghanistan, but the survey said the value of the crop may now be the equivalent of nine percent of the country's GDP.
"Opium is therefore a significant part of the Afghan economy and provides considerable funding to the insurgency and fuels corruption," said Yury Fedotov, director of the Vienna-based agency.
He called for a stronger commitment from Afghan and international partners "to turn this worrying trend around."
Income from opium finances weapons and equipment purchases for the Taliban.
Afghanistan provides about 90 percent of the world's opium, the raw ingredient for heroin. The U.N. and the Afghan government have long tried to wean the country off the lucrative crop.
The largest areas of opium poppy cultivation are in the violent south of Afghanistan, where it can be hard to make money on legal crops and where criminal networks exist to buy and sell the poppy crop.
Most farmers surveyed said they were primarily motivated by the high prices gained by opium poppy cultivation, particularly in comparison with wheat, which suffered a fall in price last year.
The survey showed that 6,400 tons (5,800 metric tons) of opium were produced last year, in comparison with 4,000 tons (3,600 metric tons) in 2010.
It said rising opium prices drove Afghan farmers to increase cultivation of the illicit opium poppy plants by 7 percent in 2011, despite a major push by the Afghan government and international allies.
Most of the opium from landlocked Afghanistan is shipped through Iran and Pakistan. Russia, which has around 2 million opium and heroin addicts, is also a principal route for drugs headed for Europe.
Moscow has repeatedly urged the U.S. military to take stronger action against Afghan drug labs. Russia has also trained several hundred Afghan counternarcotics agents.
"Counternarcotics is not the exclusive domain of specialized units alone, but the shared responsibility of everybody concerned with security, stability, governance and development in Afghanistan and the wider region," Fedotov said.