Juppé told journalists that with six French hostages currently being held by Al-Qaeda in the Islamic Maghreb (AQIM) in the region "we are clearly a target".
"We can help with logistics or training but there is no question of putting French soldiers on Malian soil."
Map of Mali
France, which has soldiers in the region stationed in Dakar and Ivory Coast, has twice attempted to intervene to save the hostages in the region, both times with disastrous results.
In July 2010 a French hostage was killed in retaliation for a botched rescue bid, and in January 2011 two Frenchmen were killed in the Malian desert as French special forces and Niger troops attempted to save them.
Juppé expressed concern over the role of armed Islamist groups fighting alongside the Tuareg rebels, in an ambiguous relationship which has the various groups controlling northern Mali since fabled Timbuktu fell on Sunday.
"It appears that this extreme Islamist/Jihadist faction is taking the upper hand among the different Tuareg factions," he said.
Juppe was speaking from Dakar ahead of the inauguration of new Senegalese President Macky Sall.
The ceremony is to be followed by a meeting of the 15-nation Economic Community of West African States who will rule on whether to hit Mali with heavy sanctions as a 72-hour deadline for the junta to restore democracy ran out.
"There is reason to believe the political side can be resolved. Then there is the military question because it seems the Tuareg offensive is moving south," said Juppé.