Militants threatening to kill three kidnapped U.N. workers said Sunday they handed over a list of 26 prisoners, some possibly held by the United States at Guantanamo Bay (search), who they would take in exchange for the hostages.

A purported spokesman for the Taliban (search) splinter group claiming to hold the three foreigners also said it might drop its other demands, which include a U.N. withdrawal from Afghanistan.

Ishaq Manzoor told The Associated Press that the list was given to Afghan officials during talks at a secret location on Sunday afternoon.

A three-strong government delegation asked for two days to look for the prisoners and find out whether they are in Afghanistan or outside, and if in Afghanistan where they are being held, Manzoor said in a telephone call.

The talks could resume on Tuesday, he said.

Neither the United Nations (search) nor the government have confirmed any contact with the kidnappers, though Afghan officials insist they are making progress toward the hostages' release.

Another spokesman for the Jaish-al Muslimeen, or Army of Muslims, said it was represented in the talks by two businessmen acting as go-betweens.

Sadir Momin said the group was "hopeful that the government and the United Nations will accept some of our demands. It is likely that we may relax some of our conditions."

The group has previously said that some of the prisoners it wants freed may be in Guantanamo Bay, Cuba or at U.S. and Afghan jails in Afghanistan. It has also demanded that the United Nations and British troops withdraw from Afghanistan.

Momin didn't say which of these demands could be eased and none of the the militants' claims could be independently verified.

The kidnapping of Annetta Flanigan of Northern Ireland, Angelito Nayan of the Philippines and Shqipe Hebibi of Kosovo was the first against foreigners in Kabul since the fall of the Taliban in 2001.

The militants released a videotape of the hostages last Sunday fueling concern that they are copying the tactics of insurgents in Iraq.

The group says Flanigan is ailing and that all three are suffering from cold and a diet of little more than cookies.

U.N. spokesman Manoel de Almeida e Silva said the concern of relatives, friends and colleagues was increasing "every day, every hour and every minute."

"The best response for their need of medical attention is their immediate release," Almeida e Silva said.

Separately, a wealthy Kosovan businessman claiming to speak for a group of friends and associates of Hebibi arrived in Kabul with his own initiative to seek her freedom.

Behgjet Pacolli told AP that he was seeking to contact the kidnappers through tribal, factional and religious leaders and already had "a very, very convincing indication" that she was alive.

Pacolli said he believed the three were being held separately in the Kabul area, but declined to elaborate. He insisted he was not offering money to secure Hebibi's release.

The commander in chief of the Afghan armed forces, Bismillah Khan, condemned the abduction Sunday as "against the culture of Afghanistan."

President-elect Hamid Karzai (search) also renewed his condemnation of the kidnapping on Saturday, when he received a visit from Pakistani President Gen. Pervez Musharraf.