Ghislaine Dupont and Claude Verlon of Radio France Internationale (RFI) had travelled yesterday to the northern city of Kidal to interview a spokesman for the Tuareg separatist group the National Movement for the Liberation of Azawad (MNLA), and were abducted outside his home, according to their employer.
RFI said MNLA spokesman Ambery Ag Rhissa said he heard commotion outside and "saw the kidnappers put the journalists into a beige 4X4".
"This was the last time that the journalists were seen alive," said Marie-Christine Saragosse, CEO of France Media Monde, which owns RFI.
Hollande expressed "his indignation over this despicable act", said a statement from his office.
More From This Section
The French leader, who sent troops to Mali in January to oust Islamist rebels from the north, has called a meeting of his ministers for Sunday to establish "jointly with Malian authorities and UN forces, the circumstances of the killings".
The UN Security Council members also "strongly condemned" the slaying of the journalists and "reiterated their full support" for the UN mission in Mali, a statement said.
The fatal kidnapping occurred just days after four Frenchmen held hostage in neighbouring Niger were freed reportedly for a huge ransom, a claim France denied.
The exact circumstances of the journalists' deaths are not yet known.
French army spokesman Colonel Gilles Jaron told AFP that French forces in Mali, alerted about the kidnapping, immediately sent out a patrol and two helicopters.