KABUL — Afghan President Hamid Karzai accused the United States of launching a drone strike that killed a 2-year-old child Thursday and vowed to not sign a long-term security agreement if similar attacks continue.

In a statement, Karzai said a suspected U.S. “pilot-less aircraft” fired into a house shortly before noon in Helmand province, killing the child and wounding two women. He said the information was relayed to him by Mohammad Naem, the governor of the province.

Spokesmen for the U.S.-led coalition did not respond to requests for comment. The U.S. Embassy in Kabul referred questions to the international coalition.

The allegations are likely to stoke tension over Karzai’s reluctance to endorse a plan that would allow several thousand U.S. troops to remain in Afghanistan after 2014.

After a year of negotiations, the Obama administration thought it had finalized an agreement with Karzai last week to allow up to 15,000 foreign troops to stay in Afghanistan to train and assist its military.

But Karzai has been reluctant to sign it, saying he first wants assurances that the United States won’t meddle in Afghan elections next year, will cease military raids on Afghan homes, and will help start peace talks between Karzai’s government and Taliban insurgents. For the latter, he has demanded that the United States release 17 Afghan prisoners from the U.S. detention center at Guantanamo Bay.

Now, Karzai has added a reduction of U.S. airstrikes to his list of demands. It was unclear from his statement whether he was calling for an end of all drone strikes or just those attacks that target Afghans’ homes.