Afghanistan on Monday welcomed greater NATO assistance in tackling its massive drugs trade, which supports an extremist insurgency, saying there had already been some successful joint operations.

Afghan police eradication teams started ripping up opium fields in main farming areas in the south, also insurgent hotspots, about 10 days ago, Deputy Interior Minister Daud Daud told reporters.

These are where teams need military support and protection from gunmen who guard lucrative poppy fields and last year killed several policemen.

"In the past three years we have been repeatedly asking the international community, the international forces that are in Afghanistan, to take part with us in fight on narcotics," Daud said.

"Fortunately today we have received positive responses, we welcome this. We have initiated some pilot joint operations in the past three months with NATO which have been very successful," he said.

One resulted in the capture of a trafficking network in the southwestern province of Farah three days ago, he said, without giving details.

Afghan forces also needed international troops to clear areas of insurgents so that "we can go in and eradicate opium fields," he said.

The minister said, however, that his government did not want troops to kill suspected drug traffickers, who should instead go before court.

NATO's top commander US General John Craddock suggested last month that the 55,000-strong International Security Assistance Force should be able to "attack directly drug producers and facilities throughout Afghanistan."

His remarks caused a stir and were later toned down with a spokesman saying that ISAF forces would go after drugs facilities and facilitators "where they provide material support to the insurgency."

NATO civilian spokesman in Kabul, John Coppard, said the alliance's support for the counter-narcotics effort in Afghanistan included providing intelligence, training, logistics and security back-up.

The alliance would not, however, get involved directly in eradication.

Afghanistan produces 90 percent of the world's opium, which supplies heroin to Europe, Central Asia and the Middle East and also gives Taliban insurgents money with which to buy weapons, according to officials.