Karzai, who is seeking more guarantees including additional assurances to protect civilians before signing the strenuously negotiated security agreement with the United States, said Thursday a suspected U.S. drone strike in Helmand province killed a 2-year-old and injured two women, the Washington Post reported.
The Karzai statement said the information about the drone strike was conveyed to him by Helmand Gov. Mohammad Naem, the Post said.
The report said there was no response to requests for comment from the U.S.-led coalition in Afghanistan.
The BBC quoted the Afghan Islamic Press news agency as saying the alleged U.S. raid struck a house in the Faqiran village in Garmser district.
The New York Times said it was not known whose drones were involved as both British and American forces use them in the Helmand area.
The bilateral security agreement will set the terms for the number of U.S. troops that will remain in Afghanistan post-2014 after the current NATO and U.S.-led forces complete their withdrawal from Afghanistan. Any residual U.S. troops would be involved mostly in training Afghan forces, although some of them may also be conduct counter-terrorism operations.
The agreement, which the United States insists needs to be signed by Karzai before the end of this year to allow for further planning, was approved last week by Afghanistan's grand assembly of elders at their Loya Jirga. However since then, Karzai has said the agreement can only be signed by Afghanistan's new president after elections in April.
The agreement took about a year to negotiate and required even last-minute talks before a final draft could be concluded for consideration by the Loya Jirga.
But with Karzai's reluctance, the fate of the agreement remains in question. Karzai also has demanded further assurances that the United States won't interfere in the April elections, its troops will stop raids of Afghan homes and assist the Karzai government in starting peace talks with Taliban insurgents.
The Post said as part of the help in the starting the peace talks, Karzai also wants the United States to release 17 Afghan prisoners from the Guantanamo Bay detention center.
In his latest statement on the Helmand strike, Karzai said: "This attack shows that American forces are not respecting the life and safety of Afghan people's houses," adding innocent Afghan people have become victims of the war "under the name of terrorism" and that they have "had no safety in their homes."
The Afghan leader said he will not sign the security agreement if such "oppressions by foreign forces continue."
The Post quoted coalition commanders that they think Karzai is using allegations of civilian deaths for political purposes.
Earlier this week, Karzai told visiting U.S. national security adviser Susan Rice American troops should no longer enter Afghan civilian homes.
The administration of U.S. President Barack Obama has said if the security agreement is not signed by the year-end deadline, it will be forced to choose the zero option of not leaving any troops post 2014.
The Post said many Afghan leaders are concerned Afghan security may be affected by Karzai's stand as the security agreement will bring $4 billion in annual U.S. and coalition funding for the Afghan military.
Speaking to the Wall Street Journal, U.S. Marine Corps Gen. Joseph Dunford, the top commander of the coalition forces, warned about the consequences of Karzai's failure to quickly sign the security agreement.
"The uncertainty and the lack of confidence about the post-2014 environment has had an adverse effect on the people in some very real ways, whether it be the flight of young people who try to leave the country, whether it be plunging real-estate prices, the rate of the Afghani" currency, the general said.