War-torn Afghanistan is by far the world's largest producer of opium. It supplies 90 percent of the heroin sold in Europe.
Thomas Schweich, the deputy assistant secretary for international narcotics and law enforcement, said that despite the big jump in cultivation, an international counternarcotics strategy for Afghanistan launched in 2005 remained effective "though it definitely needs sharpening and refining."
The counternarcotics campaign, driven largely by Britain and the United States, has resulted in an enormous sum of money being injected into programs to cut Afghanistan's dependence on drug trafficking.
Recent reports suggest, however, that there has been a 78 percent increase in the amount of land planted with opium poppies this year.