KABUL: A US airstrike in eastern Afghanistan killed 11 civilians, local officials said Wednesday, sparking condemnation from President Hamid Karzai who has often criticised the conduct of Nato forces now leaving the country.

Civilian casualties caused by the US-led military coalition during the war against Taliban insurgents have been one of the most contentious issues in the 13-year combat campaign that will end by December.

“As a result of a US aerial bombardment ... 11 civilians, including two children and two women, were killed, and 12 more injured,” said a statement from the presidential palace.

“President Hamid Karzai condemns in the strongest terms the bombardment by American forces.” It added the strike on Tuesday occurred in the Narang district of Kunar, one of the country's most volatile provinces. Kunar borders Pakistan, where many Taliban allegedly seek shelter.

Nato's International Security Assistance Force (Isaf), which often stresses that avoiding civilian casualties is a major priority, said it was “currently looking into the circumstances” of the operation.

It added that a separate “precision strike” elsewhere in Kunar on Tuesday resulted in the death of one armed militant and no civilian casualties.

Abdul Hadi Sayedkhil, the police chief of Kunar, told AFP that a joint Afghan-Nato patrol was ambushed in Narang by militants.

“The foreign forces called for air support and as a result of bombardment a number of militants and civilians were killed. We are investigating the incident,” he said.

Nato mission winds down

Saleh Mohammad, a survivor being treated in hospital in the provincial capital Asadabad, said there had been two waves of bombings.

“Four of our villagers were on their way back home from work when airplanes bombed them,” he told AFP.

“When people went to the area to collect their bodies or take the wounded people to hospital, we were bombed again. Dozens of people, including women and children, were killed or wounded.”

While misguided US air strikes have often triggered Karzai's fury and occasional street protests, the UN mission in Afghanistan says Nato is now responsible for only one per cent of all civilian deaths in the conflict.

Karzai, who has served since the Taliban regime was ousted in 2001, is due to step down as soon as a prolonged dispute over the presidential election result is resolved.

The inauguration was due on August 2, but has been repeatedly delayed as both Ashraf Ghani and Abdullah Abdullah claim victory in the fraud-tainted vote.

Karzai has used his last days in office to take populist stances on issues such as civilian casualties and in calling for the hanging of gang-rapists who were given a summary trial before being sentenced to death on Sunday.

The UN is leading efforts to save Afghanistan's first democratic transfer of power by trying to persuade the two poll rivals to agree on a power-sharing deal.

About 40,000 Nato combat troops are deployed in Afghanistan, with 12,000 expected to remain into 2015 on a training and support mission as local soldiers and police take on the Taliban.