Kabul, Afghanistan ? The new Afghan government has “largely failed” in its 4-month-old effort to eradicate the opium poppy crop in Afghanistan, which in recent years became the world’s biggest producer of the raw material for heroin, U.N. crop experts reported Sunday.

Their figures show the 2002 crop, close to the high levels of the late 1990s, could be worth more than $1 billion at the farm level in Afghanistan.

“That’s a big chunk of GDP,” said Hector Maletta, a spokesman for the U.N. Food and Agriculture Organization. This impoverished nation’s gross domestic product (GDP) for 1999, the latest estimate available, was put at $21 billion.

By the late 1990s, Afghanistan was supplying 70 percent of the world’s opium. Then, in 2000, the Taliban government banned poppy cultivation, and U.N. and U.S. drug agencies determined that this led to an almost total 96 percent reduction in acreage devoted to the crop in the 2001 growing season.

But the U.S.-led war that ousted the Taliban late last year prompted Afghan farmers to plant poppy again over tens of thousands of acres.

In April, the interim government of President Hamid Karzai announced an eradication program. Farmers would be compensated with $500 per acre for destroyed poppy, the government said. That’s only a fraction of the estimated $6,400 per acre of gross income a farmer can earn on poppy, according to the FAO report.

The government efforts failed despite pressure from the United States, Western Europe and other countries that fear a sharp rise in the supply of heroin. Only relatively small patches of opium in several regions of Afghanistan were destroyed.

The great bulk of heroin produced from Afghan opium is used by addicts in Europe. The British government, in particular, has pressured Karzai to crack down, as did Iranian President Mohammad Khatami on a visit to Kabul last week. Iran has an estimated 2 million opium and heroin addicts.

The U.N. poppy forecast came in a section of a joint report by the FAO and the U.N. World Food Program assessing all Afghan crops.

It estimated that 225,000 acres of poppy were planted, and 150,000 to 175,000 acres have been or will be harvested.

The U.N. specialists predicted an even larger crop next year. “The returns and employment opportunities are high and the risks are seen to be low given the large numbers of farmers involved and the perceived improbability of prosecutions,” they wrote.