A United Nations report released yesterday shows that opium cultivation has spread to all 32 provinces, making narcotics the main engine of economic growth. The opium economy, valued at $2.8 billion (£1.55 billion), represents 60 per cent of Afghanistan’s gross domestic product. Presenting the findings, Antonio Mario Costa, executive director of the United Nations Office on Drugs and Crime, said:

“With 131,000 hectares (324,000 acres) dedicated to opium farming this year, Afghanistan has established a double record — the highest drug cultivation in the country’s history, and the largest in the world. “Corruption in the public sector, the diehard ambition of local warlords and the complicity of local investors are becoming a factor in Afghan life,” he said.

Despite the huge increase in the land set aside for farming poppies — which supply the main ingredient for heroin — the actual growth in production from 2003 was only 17 per cent because of bad weather and disease. Even so, the total output of 4,200 tonnes of opium was only marginally below the record 4,600 tonnes harvested under the Taleban in 1999 and represents 87 per cent of world production of opium.

Most of the drugs, turned into heroin using imported chemical precursors, are smuggled across the Pakistan border, where Taleban and al-Qaeda forces in hiding demand protection and transit fees. The narcotics are eventually delivered to the Netherlands for distribution across the Continent.

The drugs explosion in Afghanistan runs counter to trends elsewhere in the world, where output is decreasing on every continent. According to the UN agency, cocaine production in the Andes region has fallen by 30 per cent in three years, and in South-East Asia opium production has decreased by 75 per cent.

Signor Costa said that it would be an error to abandon Afghanistan to opium after the country had been reclaimed from the Taleban. He added that opium cultivation, which now involves 10 per cent of the country’s population, could “ultimately incinerate everything — democracy, reconstruction and stability”. Nato and the coalition forces are under pressure to take tougher action against the traffickers.

Bill Rammell, a British Foreign Office Minister, said: “A change is taking place. Troops will now destroy seizures and hand over suspects. We need to increase the number of arrests and send a strong message to police and government officials that it is not business as usual.”

Britain is leading efforts to fight the drugs trade, as part of moves to establish democracy in Afghanistan. It has earmarked £70 million for a three-year campaign, already under way, to crush the heroin trade.

Mr Rammell confirmed that Britain would fully back Hamid Karzai, recently elected President, who has made the clampdown on drugs a priority. As part of the strategy, the Government is hoping to create alternative livelihoods for farmers, although persuading them to change crops will not be easy when for one hectare of opium they can receive ten times as much as they get for wheat. Britain is also helping to create an effective criminal justice system by training investigators, prosecutors and judges, and giving advice on building high-security court and prison facilities.

Yesterday the United States confirmed that it would spend an extra $780 million next year on the fight against drugs in Afghanistan by destroying poppy fields and providing alternative employment.