The tractor roared through the field, the plough tearing through the valuable poppy crop as the farmer looked on. A helicopter searched for insurgents and armed police stood watch, their uniforms replaced by robes and turbans to make them less conspicuous.

“The people are unhappy with this eradication campaign; if it goes on they will all join the Taleban,” Dilbar, a poppy farmer in Helmand province, told The Times.

The prospect of such a surge in Taleban numbers is bad news for the 5,000 British troops based in Helmand and 1,400 more heading there after the announcement by Des Browne, the Defence Secretary. The fiercest fighting since the Taleban were overthrown in 2001 came last year, with more than 4,000 people killed, and intelligence reports predict a new offensive this spring.

Poppy eradication is a double-edged sword. Afghanistan provides nine out of every ten grams of heroin sold on the streets of Britain, and officials are determined to stamp out poppy growth. Yet a successful campaign would leave many unemployed as potential recruits for the Taleban.

Afghans, ever the pragmatists, have devised their own solution. “We leave some fields without destroying the poppy so everyone is happy . . . otherwise they will go and support the Taleban,” said Aminullah, 21, a policeman with the eradication force in Helmand.

Although 90 per cent of Helmand’s arable land is turned over to poppy growth, only 550 hectares (1,400 acres) were destroyed in the first week of the campaign. With three months left until harvest the police know that they are fighting a losing battle.

Farmers take huge risks to grow poppy as the market price is 20 times that of wheat. But without aid they have little choice and when the crop is destroyed they are crippled by debt, often having borrowed heavily from landlords to plant the crop. Landlords make no concessions for eradicated crops and the farmers are still expected to pay off their loans.

Smugglers who take the drug out of Afghanistan are also rewarded handsomely for their trade. Very few, if any, smugglers or landlords have been punished, and in southern Afghanistan operate virtually beyond the law. “It will be impossible for us to eradicate the entire poppy. We will need months and months and the poppy will be ready for harvest in only three,” Aminullah said.

In Babaji, a village of mudwalled houses and winding dirt tracks five miles (8km) from Lashkar Gah, the capital of Helmand province, eradication was meant to be in full swing.

“We are growing poppy because we don’t have any other options,” said Abdullah, a poppy farmer, as tractors ploughed part of his field. Over sweet green tea Abdullah, 35, had persuaded a member of the local shura, or council, to leave some crops. The shura member then spoke to the eradication agents and Abdullah’s most valuable crops were saved.

In the district of Panjwayi, in neighbouring Kandahar province, where Nato troops fought the largest antiTaleban battle last September, the agents are reluctant to leave poppy fields untouched.

In the village of Haji Habib police apologised to farmers as the tractors destroyed fields of poppy. “We started here because the village is a Taleban village,” Bismallah Jan, 35 a policeman, said. “But we still feel bad we are destroying their livelihoods.”

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