KABUL, Afghanistan – In twin blows to American efforts to wage war and negotiate peace in Afghanistan, President Hamid Karzai on Thursday demanded a pullback of NATO troops from rural areas as part of a sped-up overall withdrawal while the Taliban movement declared a suspension of dialogue with the United States.

In practical terms, both developments might prove largely symbolic. Karzai does not have the power to enforce specific demands as to where Western troops are deployed, and U.S. contacts with the Taliban were only in the early stages.

However, taken together, the moves point to a rapidly souring mood on the part of two major players in the conflict and to a growing sense of disarray in the American-led coalition’s plans to find a way out of this decade-old war.

The Afghan leader’s call for coalition forces to abandon outposts in the countryside was explicitly tied to the shooting rampage allegedly carried out by an Army staff sergeant in a rural patch of Kandahar province Sunday, which left 16 civilians dead, including nine children.

Karzai’s office said he told visiting Defense Secretary Leon E. Panetta that American troops should be garrisoned only in large installations, not in small bases like the one in Kandahar’s Panjwayi district where the accused shooter was posted.

“Afghanistan’s security forces have the capability to provide security in the villages of Afghanistan,” said the statement from the presidential palace.

That demand, however, raises the prospect that Taliban fighters could move in the upcoming fair weather “fighting season” to recapture strongholds in the countryside of southern Afghanistan from which they were chased in 2010 and failed to regain last year.

Panjwayi, outside Kandahar city, was a case in point: a longtime Taliban stronghold where U.S. special forces had been trying to reach out to villagers and train them to fend off the insurgents.

The president also called for a significant acceleration in the handing over of security responsibilities to Afghan forces, saying NATO should wind down its combat role in 2013, a year earlier than planned. Western commanders have acknowledged that it will be a daunting challenge to bring the Afghan police and army up to a reasonable fighting standard even by the 2014 deadline.

The Afghan leader, however, asserted Afghanistan “is ready right now to take all security responsibilities,” adding: “Our demand is to speed up this process.”

Karzai’s strongly worded statement appeared to take the official entourage traveling with Panetta by surprise. The defense secretary had spoken to reporters after his meeting with Karzai without making reference to the new demands.

A senior U.S. defense official said Karzai’s approach would not be workable.

“Afghanistan is a country of villages,” said the official, who requested anonymity because he was not authorized to publicly discuss the private meeting. He added it was not clear that training and advising of the Afghan army, together with special operations raids, would be possible if Western forces were banned from countryside outposts.