The talks come after Taliban spokesman Qari Yusof Ahmadi said the militants had extended a deadline for a prisoner swap until tonight.
The Afghan government has refused to release any Taliban prisoners in exchange for the hostages.
The Taliban is also reportedly demanding that all South Korean soldiers leave Afghanistan.
South Korean President Roh Moo-hyun says Korean officials are "maintaining contact" with the Taliban and that Seoul is mobilizing "effective means" to resolve the standoff.
Some 1,000 Afghans took to the streets of Kandahar today to protest the kidnappings. Chanting anti-Taliban slogans, the protesters said the abduction of the mostly female Christian aid workers is un-Islamic.
Meanwhile, a purported Taliban spokesman said five other hostages -- one German and four Afghans -- are still alive.
But the Taliban spokesman told the French AFP news agency that the German hostage is very sick and is in and out of consciousness. It is impossible to independently verify the claim.
Two German aid workers were kidnapped on July 18.
The body of one of them was recovered on July 22. The cause of his death is not yet clear.
(compiled from agency reports)