KANDAHAR: As the world's largest opium producer, Afghanistan's steady increase has had a direct impact on global opium cultivation, which reached record levels last year, triggering “a large increase” in cheaper heroin supply around the world, the United Nations said in a report last year.

But this happened despite opium poppy cultivation in Afghanistan decreasing 19 per cent in 2015 over the previous year, after rising six years in a row, says the latest available Afghanistan Opium Survey.

The area under opium poppy cultivation in 2015 is estimated to be 183,000 hectares (ha), compared with 224,000 ha in 2014. The cultivation area had decreased for the first time since 2009.

Almost 90 per cent of Afghanistan's poppy cultivation is in the south and the west, and provinces such as Helmand and Kandahar, longtime Taliban strongholds, have become synonymous for poppy cultivation.

As opium production rises, so does Afghanistan's own drug addiction problem.

Estimates put the number of heroin addicts in the country at between 1.5 million and 2 million in a population estimated at around 30 million.

And the unchecked Afghan opium production is also blamed for rising drug addiction in neighboring countries, including the former Soviet republics to the north, Iran to the west, and China and Pakistan to the east.