KABUL President Barack Obama expressed "deep regret" over an air strike in Afghanistan that killed nine children, the Afghan presidency said on Thursday.
Afghan President Hamid Karzai's palace said in a statement that Obama had offered his condolences during a video conference the previous evening.
The White House in Washington said the two leaders spoke for an hour and that Obama stressed to Karzai that he and top U.S. General David Petraeus take such incidents seriously.
"President Obama and President Karzai agreed that such incidents undermine our shared efforts in fighting terrorism," the White House.
Their conversation also covered efforts toward preparing for Afghanistan to take the lead on security in the country and the beginning of U.S. troop reductions in July.
Civilian casualties caused by NATO-led and Afghan forces hunting insurgents are one of the biggest complaints of ordinary Afghans and have driven a wedge between President Hamid Karzai and his main ally, Washington.
There have been at least four incidents of civilian casualties in eastern Afghanistan in the past two weeks in which Afghan officials say more than 80 people have died. Karzai and Afghan lawmakers have strongly criticized the attacks.
Petraeus, the commander of U.S. and NATO forces, delivered a rare and candid apology late on Wednesday for the raid in eastern Kunar province the previous day in which nine children gathering firewood were gunned down by attack helicopters.
On Thursday, the NATO-led International Security Assistance Force (ISAF) distributed CDs with a recorded television statement in English and Afghanistan's two main languages from Petraeus's deputy, U.S. Lieutenant General David Rodriguez.
"On behalf of the coalition ... I want to offer my sincere apology for the killing of nine children in Dara-ya-Pech district in Kunar province," said Rodriguez, who commands day-to-day operations in Afghanistan.
"The helicopters identified what they thought were insurgents, killing nine ... immediately we sent an assessment team, the assessment team confirmed the worst, we had made a terrible mistake."
AFGHANS SAY APOLOGY NOT ACCEPTED
While U.S. and NATO-led forces have acknowledged killing civilians in the past, the apologies from such senior U.S. officials indicate how much civilian deaths are hampering efforts to end a war now in its 10th year.
ISAF acknowledgments of civilian casualties over the past year have normally consisted of set statements that also highlight that insurgents are responsible for the majority of civilian deaths.
Civilian casualties in Afghanistan rose 20 percent to 6,215 in the first 10 months of 2010 compared with 2009, according to the United Nations, with insurgents responsible for more than three-quarters of those killed or wounded.
But it is those deaths caused by international troops which anger ordinary Afghans the most. While they do not condone them, many Afghans say militants attacks would not happen if international troops were not in Afghanistan.
Some felt the apologies were not enough.
"It is not the first time they have killed our poor and innocent people, we don't accept their apologies," said one angry Kabul resident, Enyatullah Khan.
"They have apologized in the past but continue killing our people again and again."
Habibullah, another Kabul resident said: "NATO cannot control this country with bombardments. We have experience of 30 years of war ... bombardments are not the solution."
(Additional reporting by Abdul Saboor, and Patricia Zengerle in Washington; editing by Paul Tait, Jon Hemming and Mohammad Zargham)