Afghanistan's Taliban insurgents and South Korean officials began a new round of talks on Thursday to secure the release of 19 Korean church volunteers, the first since two women hostages were freed this week.

"The talks started again today at 3 o' clock (1030 GMT). We hope they achieve a good result," Taliban spokesman Qari Mohammad Yousuf said.

The Taliban on Monday freed two women hostages, the first since they seized 23 Koreans from a bus in Ghazni province on the main road south from the capital Kabul last month. They have killed two male hostages.

The insurgents said they had freed the two women as they were seriously ill, and also as a gesture of goodwill, to encourage the Afghan government to free rebel prisoners in exchange for the remaining captives, 16 of them women.

The talks between the Taliban and the Korean officials were taking place at the Afghan Red Crescent Society building in Ghazni, facilitated by the International Committee of the Red Cross (ICRC).

"I can confirm the talks started again a short while ago," ICRC spokesman Jean Pascal Moret said.

The Taliban have threatened to kill the hostages if the demand to free insurgent prisoners is not met.

The Afghan government has refused to let Taliban prisoners go, saying that would just encourage more kidnapping.

Since the two women hostages were freed on Monday, there had been no further talks to release the remaining hostages.

Moret said the talks on Thursday were the first facilitated by the ICRC since the release of the pair.