Khial Muhammad, an Afghan parliamentarian and a member of the negotiating team, confirmed the women's release in an interview with RFE/RL's Radio Free Afghanistan.
He said he is optimistic that negotiations to secure the release of the remaining 19 hostages will succeed.
"I am 95 percent sure that if God’s willing, then the others will not be killed," Muhammad said.
A tribal elder from Ghazni Province, Haji Zahir, received the two women earlier today from Taliban fighters and transported them to officials from the International Federation of Red Cross and Red Crescent Societies, who in turn handed them over to South Korean officials.
A Taliban spokesman, Qari Yusof Ahmadi, said the two women, who are said to have been ill, had been released as a "goodwill gesture."
The two women were among the remaining 21 Christian aid workers from South Korea who were kidnapped in Ghazni, in southern Afghanistan, on July 19.
The Taliban has executed two of the South Koreans, both males.
The militia says it is still demanding the Afghan government release militant prisoners in exchange for the South Koreans.
The Afghan government rejects that demand.
A South Korean negotiating team has been holding face-to-face talks with Taliban officials in Ghazni an effort to secure the release of the hostages.
The United States welcomed the release of the two women, and urged the kidnappers to free the remaining 19 hostages.
German Hostage Asks For Help
Meanwhile, a man who identified himself as a German being held hostage by the Taliban said today his captors want to kill him.
The man, who identified himself as Rudolph Blechschmidt, told the French AFP news agency that he is ill and asked the German government to help secure his freedom.
Blechschmidt was captured in Afghanistan on July 18.
(with material from agency reports)