KABUL, Afghanistan - Afghanistan's heroin-producing poppies will not be sprayed with herbicide this year despite a record crop in 2006 and U.S. pressure for President Hamid Karzai to allow the drug-fighting tactic, a spokesman said Thursday.

However, Karzai told foreign and Afghan officials this week that if Afghanistan's poppy crop isn't reduced this year he would allow spraying in 2008, according to a Western official who requested anonymity because of the matter's sensitivity.

Karzai's Cabinet decided Sunday to hold off on using chemicals for now, according to Said Mohammad Azam, spokesman for Afghanistan's Ministry of Counter Narcotics.

"There will be no ground spraying this year," Azam told The Associated Press.

He said there would be more pressure to destroy poppy crops with "traditional" techniques -- typically sending teams of laborers into fields to batter down or plow in the plants before they can be harvested.

"If it works, that is fine," Azam said. "If it does not, next year ground spraying will be in the list of options."

Fueled by the Taliban, a powerful drug mafia and the need for a profitable crop that can overcome drought, opium production from poppies in Afghanistan last year rose 49 per cent to 6,700 tons -- enough to make about 670 tons of heroin. That's more than 90 per cent of the world's supply and more than the world's addicts consume in a year.

However, Afghans are deeply opposed to aerial spraying, and Karzai has said herbicides pose too big a risk of contaminating water, killing licit crops and harming local residents. Any chemicals would have been spread at ground level, not by planes.

The decision caps months of behind-the-scenes pressure from the U.S. for Karzai to allow a technique already used in countries such as Colombia. Afghan officials have deployed similar arguments in previous years to reject spraying.

"We always said that the ground based spraying is a decision for the Afghans to make," said Joe Mellott, the spokesman for the U.S. Embassy in Afghanistan. "So we understand they are going to focus on a robust manual and mechanical program to eradicate poppies this year."

The U.S. will provide assistance in that, Mellott said, and also "if they want to use herbicide."

In December, the top U.S. anti-drug official said that poppies would be sprayed -- though he didn't say when that would happen.

"I think the (Afghan) president has said yes, and I think some of the ministers have repeated yes," John Walters, the director of the U.S. Office of National Drug Control Policy, said last month. "The particulars of the application have not been decided yet, but yes, the goal is to carry out ground spraying."

However, no top Afghan officials have said publicly that the government would carry out spraying.

Walters, on a December visit to Kabul, said Afghanistan could turn into a narco-state unless "giant steps" were made toward eliminating poppies.

U.S. and Afghan officials agree that eradication must be matched with a crackdown on traffickers and programs to help farmers switch to licit crops.

"We have done an enormous amount of alternative livelihood, but you are not going to have a full meaning of alternatives until we build a rural economy and until you can move a crop to the market," said U.S. Ambassador Ronald Neumann, referring to Afghanistan's terrible roads.

Few crops in Afghanistan can be transported far without spoiling or damage. By comparison, poppy resin, the main ingredient in heroin, is robust and can keep for years.