KABUL, Afghanistan -- After years of tightly intertwining its forces with Afghan troops, the American-led military coalition has sharply curtailed ground-level operations with the Afghan Army and police forces, potentially undercutting the training mission that is the heart of the Western exit strategy.
The new limits, which were issued Sunday and require a general's approval for any joint work at the small-unit level, were prompted by a spike in attacks on international troops by Afghan soldiers and police over the past six weeks. There was also fear that anger over an anti-Islam video could prompt more of what the coalition calls insider attacks, American officials said.
Coalition officials stressed that their officers would still be paired with higher-level Afghan units, and that the basic concept of training, advising and fighting alongside Afghan units in the field to ready them to fight on their own remained at the core of war strategy.
The advisory mission is "the way ahead. It is still valid," said Lt. Col. Richard W. Spiegel of the Army, a coalition spokesman.
"We are not stepping away from this," Colonel Spiegel added. "Things might look a little different, but we're not walking away."
Underscoring the potential for backlash over the amateurish video parodying the Prophet Muhammad, 14 people, 10 of them foreigners, were killed by a suicide bomber here in Kabul on Tuesday, bringing to at least 28 the number of deaths attributed to unrest sweeping the Muslim world as a result of the film. A spokesman for an Afghan insurgent group, Hezb-i-Islami, claimed responsibility for the bombing and said it was carried out by an 18-year-old woman.
"We claim credit for the attack by a martyrdom-seeking mujahid, an 18-year-old girl named Fatima, from Kabul, and the attack has been conducted in response to the film insulting the Prophet Muhammad and Islam," said Zubir Siddiqi, a spokesman for the group, who was reached by telephone.
Coalition officers said the order to curtail direct cooperation covers all work done with Afghan forces below the level of a battalion. An American battalion has about 700 to 800 troops, though some are larger or smaller, and is designed to be the smallest unit that can fight independent of a higher command.
But in Afghanistan, where the Taliban blend easily and often strike in small groups, most of the combat goes on far below the battalion level, with small squads of about 10 men or platoons of about 15 to 40 soldiers or Marines.
Many of the day-to-day interactions between coalition and Afghan forces, like joint patrols and meetings with village elders, also take place in small groups. Sometimes, even recreation is shared, with Afghans and foreign troops playing volleyball or working out together at one of the scores of small, shared combat outposts spread across the country.
"Clearly, we're going to be seeing less of that," Colonel Spiegel said.
But, he stressed, work at those levels with the Afghans would not cease completely. Rather, any operations below the battalion level now must be approved by one of the five coalition regional commands in Afghanistan.
Most officials insisted the change would not have a huge impact or alter the basic American strategy. "No one should interpret this as anything more than a prudent response to recent events. We remain committed to our goals and strategy in Afghanistan," said George Little, the Pentagon spokesman, speaking to reporters during a trip to China.
At a news conference on that trip, Defense Secretary Leon E. Panetta said: "We are concerned with regards to these insider attacks and the impact they are having on our forces." Gen. John R. Allen, the top NATO commander in Afghanistan, "has reflected that in the steps that he has taken," Mr. Panetta said.
Some officials, though, acknowledged the new order would sharply limit organic cooperation between junior American and Afghan officers and their troops in the field, and thus could undercut the effectiveness of the advisory mission.
Until now, they had been empowered to organize patrols or small operations. An American captain could send men from his company to reinforce Afghans in a firefight without seeking higher approval.
But now, if a young lieutenant who commands a platoon wants to take a few dozen soldiers on a routine patrol with Afghan forces, he needs approval from a two-star general who commands a division, which usually has about 10,000 service members.
How adding layers of bureaucracy will play out remains to be seen, coalition officials said, noting that the new order was only issued two days ago. The order was first reported on Tuesday by NBC News, although its report said that all partnering of forces had been cut off, not just the work done by smaller units.
But officials insisted the strategy of partnering with the Afghans to get them ready to fight on their own remained in place. "The advisory piece has not stopped," Colonel Spiegel said. "All that's really happening is that we've changed the level at which risk assessments are approved."
It was also unclear how the logistics of the new plan would work. The higher-level commands -- the battalions and brigades -- that will remain fully partnered with their Afghan counterparts are housed on sprawling bases where there is often physical distance and high walls between them and the Afghan commands.
But the smaller units those commands are composed of -- companies and platoons -- are in many places based at small outposts shared with Afghan forces. Sometimes, the two are separated by mere yards, and they often share guard duty at the outpost's gate and in its guard towers, among other duties.
How work at those outposts is supposed to continue is unclear. Colonel Spiegel said there was no "cookie-cutter solution" and each case would be considered on an individual basis.
Other support the Americans and their NATO allies provide the Afghans would remain in place, like air cover, artillery support and the airlifting of wounded Afghans on American medical evacuation helicopters.
Afghan soldiers were not reassured by such talk. Three interviewed as word spread Tuesday said their many of their units were not yet ready to fight alone -- an assessment shared by the Pentagon -- and could be in deep trouble without close coalition assistance.
The curtailment of partnered operations is "a big problem for the Afghan Army," said Maj. Salam, an officer based in western Afghanistan who asked that he only be identified by his rank and last name.
"We rely on the Americans for everything," he continued. "The army is not in a level to carry out military operations independently, we still need their support. I do not buy the lies that the MOD officials are trying to sell us and the public -- we are in the field and we know how difficult it would be for the army without Americans."
He cited an episode on Monday in which an Afghan Army vehicle struck a hidden bomb. Two soldiers were killed, and the Americans did not respond to a request to evacuate four wounded soldiers.
Instead, they had to wait for help from their own forces, which do not have medical evacuation helicopters. "It took them six hours to bring the soldiers to the hospital. One of them has lost a lot of blood, and he might die," Major Salam said.
If the Americans "abandon us," he said, "they should know that it would be the end of everything for all of us."
Habib Zahori, Sangar Rahimi and Rod Nordland contributed reporting in Kabul, and Thom Shanker in Beijing contributed reporting.
This article originally appeared in The New York Times.