President Francois Hollande says French air strikes have inflicted “heavy losses” on Islamist rebels in the West African nation of Mali.
Hollande spoke as French aircraft on January 12 bombarded the rebels for a second day.
Hollande said France had decided to act to prepare the way for the eventual deployment of an African force in Mali to reconquer territory seized by the rebels.
The French leader also announced that the authorities are boosting security inside France to protect against potential retaliation.
Officials said a French pilot had died when his helicopter was shot down by the Al-Qaeda–linked Mali rebels.
Hundreds of French soldiers are meanwhile reported to have deployed in Bamako to protect the capital.
The United Nations Security Council, European Union, and United States have all backed intervention to repel the Islamists.
The Islamists last week seized the central town of Konna, raising concerns they had launched an offensive from their northern base to capture the whole of the country.
Officials say Konna has been recaptured by government forces. Malian Interim President Dioncounda Traore, who has declared a national state of emergency, said 11 soldiers had died and some 60 were wounded in fighting over the town.
In a televised statement at the Elysee Palace, Hollande said security was being increased at French public buildings and transport infrastructure to guard against potential reprisals.
In addition to the Mali intervention, French forces were in action in the Horn of Africa nation of Somalia on January 12.
Officials said an attempt to rescue a French intelligence agent held by Somali Islamists had failed, and that two French soldiers and the agent were feared dead, along with 17 militants.
In his address, Hollande said French forces had pushed back the rebel advance in Mali, inflicting “heavy losses.”
He said France’s mission was to prepare for the insertion of an African-led force to reclaim territory held by the rebels.
"Thanks to the courage of our soldiers, we have held back the progress of our adversaries and inflicted heavy losses on them," Hollande said.
"But our mission is not over yet. I reiterate that it consists in preparing the deployment of an African intervention force, to allow Mali to get back its territorial integrity in accordance with the Security Council resolution.”
Hollande stressed that Paris had only one goal for its intervention in its former colony -- to “fight against terrorism.”
Western officials have raised concerns that Islamists could turn Mali into a base to organize attacks on the West and strengthen the influence of Al-Qaeda-linked militants in North Africa.
"I reiterate that in this operation, France is not pursuing any particular interests, other than the safety of a country that is a friend," Hollande said.
"It doesn't have any other goal than the fight against terrorism. That is why, its actions are supported by the whole of the international community and acknowledged by all the African countries."
The UN Security Council has authorized the deployment of a 3,300-strong African intervention force to help the Malian government restore order.
The 15-nation West African bloc ECOWAS has approved the immediate deployment of troops for the force.
The crisis has arisen since a military coup in Mali in March 2012. In the wake of the instability, secular Tuareg rebels seized the north of the landlocked country. Islamists took advantage of the security vacuum to make their own power grab.
With reporting by Reuters, AP, AFP, and dpa