PARIS: A French soldier was killed on Tuesday in a clash with militants in northern Mali where the French are in the midst of a critical operation, President Francois Hollande announced.    

A Defense Ministry statement said that nearly 20 extremists have been killed in the ongoing fighting.

The death of the French Foreign Legionnaire brings to two the number of French killed since France, Mali's one-time colonial ruler, launched a military intervention on Jan. 11 to push out militants who had taken over the African country's vast north.

A helicopter pilot was killed on the first day of the intervention.

The operation in a mountainous region where extremists are holed up is in its ''last phase,'' the president said.

''At this moment we have special forces who are in the north of Mali and who are intervening in a zone that is particularly delicate, which is the Ifoghas mountain range, where terror groups are holed up,'' he said during a visit to Greece.

''There was a serious clash with several deaths on the side of the terrorists, but also a death on the French side,'' Hollande said, adding that the soldier killed came from a Legionnaire parachute regiment.

The French-led operation is aimed at preventing the extremists from taking over all of Mali and destabilizing the west African region.