By Andrew North
BBC correspondent in Kabul
The Afghan leader Hamid Karzai has said the country's rampant drugs trade is a national disgrace.
Afghanistan produces 87% of world opium, the UN says
He said that if it was not brought under control, it could present a more serious threat than the Soviet invasion of Afghanistan 25 years ago.
He was addressing a large gathering of tribal elders and provincial governors and diplomats at an anti-drugs conference in Kabul.
Afghan opium production accounts for most of the world's heroin supplies.
President Karzai's was a passionate and at times angry speech.
At one point he repeatedly thumped the podium from which he was speaking, in the same hall where he was sworn in as Afghanistan's first elected leader two days ago.
He portrayed the drugs trade as a dire threat to the country's future.
"As we did jihad against the Russian invasion we should now do a
jihad against the narcotics, which have dishonoured our nation among
the international community," he said.
He told his audience it was not the opium farmers who get the real benefit - the big profits go abroad to drugs mafias, who put the money into foreign banks.
But the disgrace and dishonour, he said, comes back to Afghanistan.
President Karzai's problem, though, is how big the drugs trade has become - worth around two-thirds of the Afghan economy, according to the UN.
So a serious campaign against it risks causing violence and instability.
And although Western nations have promised extra funding for alternative sources of income, few of these programmes are under way, and none are yet making a significant difference.