Officials searched Thursday for a neutral meeting place that would be safe for both South Korean negotiators and Taliban captors to hold face-to-face talks about the release of 21 South Koreans held hostage in Afghanistan.

At an Asian security conference in the Philippines, South Korean Foreign Minister Song Min-soon and U.S. Deputy Secretary of State John Negroponte agreed to place top priority on safely freeing the hostages, ruling out a military option for ending the standoff, a South Korean official said.

But in Washington, senior State Department official Richard Boucher said the United States is not ruling out military force to free the hostages.

A delegation of South Korean lawmakers left for Washington in the latest diplomatic effort to urge the United States to help end the 15-day crisis.

Afghan officials said the Taliban captors have agreed to meet with South Korea's ambassador, but they had not yet agreed on a venue.

"If the Taliban want to come to the area where we are for the sake of these hostages, 100 percent, they will be safe," Ghazni Gov. Marajudin Pathan told a news conference.

But both sides have proposed places that could put them at risk — including the office of the provincial reconstruction team, which is run by international troops.

"The Koreans told the Taliban to come to the PRT, and the Taliban told the Koreans to come to their base," Pathan told The Associated Press after the news conference.

Purported Taliban spokesman Qari Yousef Ahmadi said the South Koreans had not requested direct talks with the militants, but the insurgents would be willing to hold such a meeting in Taliban-controlled territory.

The Taliban "want to negotiate directly with the Koreans because the Kabul administration is not sincere about releasing the Taliban prisoners," Ahmadi told The Associated Press by telephone from an undisclosed location.

A South Korean Embassy official in Kabul would not confirm any Korean efforts to hold face-to-face talks with Taliban.

Ahmadi said the remaining 21 hostages were still alive, but two of the women were very sick and could die from illness.

Meanwhile, Newsweek magazine reported a regional Taliban commander claiming to be the mastermind behind the abductions said the militants might prolong the crisis to embarrass President Hamid Karzai.

The commander, who did not give his name, said the militants want to secure the freedom of eight Taliban prisoners in exchange for all the South Korean hostages. He also said the 16 women among the captives were safe for now.

None of the claims could be independently verified. But Afghan officials have said the militants have demanded the release of local Taliban fighters from Ghazni province as well as a former militia spokesman, Mohammad Hanif.

The Afghan government has said it is opposed to a prisoner swap out of concern that it could encourage more kidnappings.

In Islamabad, a leader of a coalition of hardline Pakistani religious parties met for one hour with a five-member South Korean delegation seeking the Islamist politician's help to win the hostages' release.

Fazlur Rahman, who strongly opposes the presence of foreign troops in Afghanistan, said afterward the delegates had said South Korea was offering an early withdrawal of its troops in a U.S.-led coalition. He said in response, the Taliban should release the women captives and the sick as a "goodwill gesture."

"The abducted Koreans had been on a medical mission. They should have protection in war zones," Rahman said. "When the Korean president plans to withdraw troops before their proposed withdrawal time, the Taliban should release at least the women and those who are reportedly ill."

He did not elaborate on when South Korea was willing to withdraw its 210 troops serving in the U.S.-led coalition in Afghanistan. They are scheduled to leave in December.

The 23 Korean church group volunteers were kidnapped in Ghazni province on July 19 as they traveled by bus from Kabul to the southern city of Kandahar. The Taliban have shot and killed two men in the group.

Also Thursday, a delegation of eight South Korean lawmakers departed for Washington to "sincerely plead with the United States to take more substantial and meaningful measures to resolve this crisis," one of the group, Rep. Cheon Young-se, said.

The delegation expects to meet U.S. House Speaker Nancy Pelosi and national security adviser Stephen Hadley, as well as U.N. Secretary-General Ban Ki-moon, a former South Korean foreign minister.

Earlier South Korean efforts — including sending the presidential envoy to Afghanistan and phone calls between President Roh Moo-hyun and Karzai — failed to bend Afghanistan's refusal to respond to Taliban demands.