Fugitive Taliban leader Mullah Mohammad Omar has used the holiest Muslim holiday of the year to warn that his men will intensify their fighting in Afghanistan to "surprising" levels to drive out foreign forces.
In a message to Afghans for Id al-Fitr, which marks the end of the fasting month of Ramadan, Omar also urged NATO to withdraw its almost 20,000 troops and stop sacrificing soldiers for the US, adding the nation stood with him.
"With the grace of Allah, the fighting will be increased ... and it will be organized in the next few months," he said in a message to media also posted on the Internet and signed "Leader of the Faithful in the Afghan Resistance."
"I am confident the fighting will be a surprise for many," he said.
NATO, which took over full national command of the war against the Taliban from US forces this month, says attacks in the south have fallen since it killed hundreds of insurgents in a two-week offensive last month named Operation Medusa.
But fighting and bombings are virtually daily events and the government has warned of a rise in suicide bombings ahead of the traditional winter lull in combat.
Omar said Afghan President Hamid Karzai would face Islamic justice for cooperating with Washington.
"The Kabul puppet regime has failed to establish peace and stability as well as to control narcotics," he said, adding members of the government were involved in the opium trade.
Officials and analysts say the Taliban is partly funded by drug lords underwriting fighting and insecurity to keep the police and the law from their poppy fields and smuggling routes.
Afghanistan supplies about 90 percent of the world's opium, the raw material for heroin, and its crop is expected to jump about 60 percent this year.
Talking to reporters after Id prayers at the presidential palace, Karzai did not comment on Omar's message, but called on Afghans not to be swayed by the Taliban.
"My message to those who are being used by strangers and killing their people and their children, destroying their homes, my message is to free themselves from the grip of menace," he said.
"That menace has been destroying Afghanistan for years. I ask them to come to their country and free themselves from being used by others and work to build their country not to destroy it," Karzai said.
Meanwhile NATO-led troops and Afghan soldiers patrolled an area of western Afghanistan yesterday where factional fighting left at least 32 people dead, including a notorious warlord.
Karzai said he would send a delegation to the remote area in the western province of Herat, to "try to bring peace and calm" after Sunday's clashes.