(CNN) -- France must pull its troops from Afghanistan if it wants to ensure the well-being of five French nationals taken hostage in Niger, the head of al Qaeda's north African wing said.
"If you want safety for your citizens who are held captive by us, then you must move quickly to take your soldiers out of Afghanistan according to a specific time table that you announce officially," said Abu Musab Abdul-Wadud, the head of al Qaeda in the Islamic Maghreb in an audio message broadcast on Al-Jazeera television Wednesday.
The group has said it is responsible for the five French citizens who were kidnapped in September.
The five were among seven people linked to a French nuclear energy company who were abducted in the northern town of Arlit in Niger. The other two are from Togo and Madagascar.
Areva has been mining uranium for decades in Niger, one of the poorest countries in the world.
In a televised interview with reporters Tuesday, French President Nicolas Sarkozy urged citizens not to visit areas where al Qaeda in the Islamic Maghrib operates.
"The situation on the terrorism front is troubling. I do not want to alarm the French," he said. "But, we will not change even an iota of our policies because we are threatened."
France has already said it may begin to withdraw some troops from Afghanistan next year.
Minister Herve Morin told French radio station RTL in late October that France will begin to transfer the control of certain districts to Afghans in 2011.
"There is a fixed date by NATO in the framework of its new strategy. That is the start of 2011," he said. "In 2011, we are going to transfer a whole series of districts to the Afghans."
"At this moment, there could be the first movements or withdrawal of allied forces from Afghanistan," Morin said.
France has 3,750 troops in Afghanistan, according to NATO's International Security Assistance Force.