In a purported Taliban statement on the Internet on April 20, the Islamist militants also demanded that the Afghan government release some Taliban prisoners.
Taliban militants say they abducted a French man and woman, as well as three Afghans from the aid group Terre d'Enfance. The five disappeared on April 3, in Afghanistan's southwestern Nimroz Province.Video Of Hostages
On April 14, the Taliban released a video of the two French aid workers -- a woman who identified herself only as Celine and a man who called himself Eric -- pleading for help.
"My name is Celine. I am French. I am working for a French NGO called TDE -- Terre d'Enfance," the woman said on the video. "I have been kidnapped and I am now in the hands of the Taliban with Eric, Hashim, Hazrat, and Rasul."
The Taliban statement said that if the demands were not met, "a prompt action will be taken" against the hostages.
The authenticity of the Taliban statement could not be independently verified. But it was posted on websites often used by the Taliban, Al-Qaeda, and other insurgent groups.
The French Foreign Ministry said only that it was "analyzing" the Taliban's demand, but made no further comment. France has about 1,100 troops working as part of the 36,000-strong, NATO-led force in Afghanistan.Bargaining With Kidnappers
Afghan President Hamid Karzai said in March he would make no more prisoner swaps after what many saw as a botched exchange of Taliban prisoners for kidnapped Italian journalist Daniele Mastrogiacomo.
Mastrogiacomo was kidnapped in March. He was freed after two weeks when Kabul released five senior Taliban prisoners. His Afghan driver and translator were beheaded. Critics said the Mastrogiacomo case encouraged the Taliban to take more hostages.
The new Taliban demands came as the group pledged to launch fresh attacks.
Reuters quoted a Taliban commander, Mullah Hayatullah Kahn, as saying that the group's fugitive leader, Mullah Mohammad Omar, has urged his followers to step up attacks on foreign and Afghan troops.
Meanwhile, AFP quoted a purported Taliban spokesman, Qari Yusof Ahmadi, as saying that militants plan to launch fresh attacks in Afghanistan's relatively peaceful north.