Face-to-face talks between the Taliban and South Korean officials over the fate of 21 hostages will not happen unless the officials travel to Taliban territory or the U.N. guarantees the militants' safety elsewhere, a purported spokesman said Sunday.

The spokesman, Qari Yousef Ahmadi, said the militants had talked to the Korean officials "many times" over the phone the last three days but that there had been "no results."

"We gave them two choices: either come to Taliban-controlled territory or meet us abroad," Ahmadi said from an unknown location. "They accepted these options and told us, 'We are trying to persuade the U.N. to give you a guarantee to meet us in another country."'

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"The Koreans also said if the UN did not agree to give the Taliban a guarantee we will come to your areas to meet. They have not done any of the above promises yet," he said.

A United Nations spokesman said the international body was "fully supporting" efforts by the South Korean and Afghan governments to resolve the crisis.

"We are obviously aware of the unconfirmed reports suggesting that those holding the aid workers have requested our assistance to meet with the South Korean delegation at a neutral venue, but we have not been approached directly on this issue," said Dan McNorton of the U.N. Assistance Mission in Afghanistan.

Twenty-three South Koreans from a church group were kidnapped by the Taliban on July 19 while traveling from Kabul to Kandahar to work on medical and other aid projects. Two of the male hostages have been executed. Among the remaining 21 hostages, 16 are women.

The Taliban have demanded that 23 militant prisoners being held by Afghanistan and at the U.S. base at Bagram be freed in exchange for the Koreans' lives, but the Afghan government has all but ruled that option out, saying it will not allow kidnapping to become a lucrative business.

An official at the Korean Embassy in Kabul said the location of a potential meeting between the Koreans and the Taliban was not important. Asked if paying a ransom is an option, he declined to comment. He spoke on condition he not be identified in line with embassy rules.

South Korea has appealed to the United States to get more involved in the negotiation process, and the Koreans are expected to be one of the topics on the agenda of Afghan President Hamid Karzai and U.S. President George W. Bush when they meet at Camp David, Maryland, on Sunday and Monday.

Ahmadi said the Taliban have been waiting for negotiations to start and have extended many deadlines for the Koreans' lives.

If an agreement is not reached for in-person negotiations, then the Taliban will not be responsible for "anything bad" that happens to the hostages, Ahmadi said.

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