An international human rights group criticized NATO-led troops in Afghanistan, saying their tactics increasingly endanger civilians and are turning the population against the Western alliance.

NATO's top commander apologized Saturday for civilian deaths caused by fighting between Taliban militants and NATO forces earlier in the week, but said insurgents endanger civilians by hiding among them.

"Sadly, in asymmetric warfare, when you're battling an insurgency, typically the insurgents do not play by the same rules that we would like to play by," U.S. Gen. James L. Jones said.

A purported statement by the Taliban leadership, meanwhile, said the hardline militia has ruled out talks with President Hamid Karzai's government as long as foreign troops remain in the country.

The New York-based Human Rights Watch complained Friday that NATO's recent operations have killed dozens of civilians, but it also criticized the Taliban and other insurgents for putting civilians at risk "by using populated areas to launch attacks on NATO and Afghan government forces."

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"While NATO forces try to minimize harm to civilians, they obviously are not doing enough," said Sam Zarifi, the group's Asia research director. "NATO's tactics are increasingly endangering the civilians they are supposed to be protecting and turning the local population against them."

He spoke on the same day that the International Red Cross urged all sides in the Afghan conflict to spare civilians.

Jones, the NATO commander, expressed regret for civilian deaths but said Taliban fighters use civilians as human shields and said that in the heat of battle it can be difficult to separate the two.

The death of a civilian "is something that causes anybody in uniform to lose a lot of sleep," Jones said at a news conference at Bagram, the largest U.S. base in Afghanistan.

His comments came four days after clashes between NATO-led troops and insurgents in the south that Afghan officials say killed 30 to 80 civilians, including women and children. NATO said its initial investigation found 12 civilians killed.

The 32,000-strong NATO-led force took command of security operations in Afghanistan last month. The alliance has been battling resurgent Taliban militants in the south and east in the worst upsurge of violence since the 2001 U.S.-led invasion ousted the Taliban.

A Taliban statement e-mailed to The Associated Press by purported militia spokesman Muhammad Hanif dismissed Karzai's offer for talks Friday and called his administration a "puppet government." Hanif's exact ties to Taliban leaders are unclear, and it was not possible to verify the statement's authenticity.

"We say even today that there is no possibility of any talks when the country is under occupation," it said. "Any talks with aggressors would amount to selling the country."

On Friday, Karzai reiterated to reporters that he was ready to negotiate with Taliban leader Mullah Omar if the fugitive stops receiving support from neighboring Pakistan. Karzai says Omar is hiding in the Pakistani city of Quetta, while Pakistan says he is in Afghanistan.

Over the past two years, hundreds of Taliban supporters, including some senior officials, have reconciled with Karzai's government, but there is no indication that high-level talks with the rebel leadership have occurred.

Karzai made a similar offer in an interview with AP last January, telling Omar to "get in touch" if he wanted to talk peace, but fighting has since escalated sharply.

Human Rights Watch argued that NATO is relying too much on aircraft to attack insurgent positions. In June, the U.S. Central Command reported 340 airstrikes in Afghanistan, double the 160 strikes in Iraq in the same month, the group noted.

"NATO should reconsider the use of highly destructive but hard-to-target weaponry in areas where there is a clear risk of considerable civilian casualties," Zarifi said, referring to aerial bombs and missiles.

Maj. Luke Knittig, the spokesman for NATO's International Security Assistance Force in Afghanistan, said that "airpower is used extensively because it is an advantage and it can be decisive at a close fight."

But, he added, "its careful application is mandatory."

"We heed the calls for maximum caution in our operations to minimize civilian casualties," Knittig said, adding that NATO provides medical care to injured civilians and financial assistance to affected communities.