French Defense Minister Jean-Yves Le Drian said on Thursday that 1,400 French soldiers were deployed in Mali where they carried out ground assaults as Islamist rebels resisted week-long air strikes.

"This morning, there are 1,400 French troops. There were lightings yesterday in the ground and by air... and there are right now," the minister was quoted by the daily Le Parisien as saying.

In Face of strong rebels' resistance, French troops broadened their operation and launched their first ground fighting against al-Qaeda affiliated insurgents in Mali on Wednesday after they seized Diabaly, a central town of strategic importance, where are located "the most organized, determined and armed groups," the minister said in a previous interview.

France, which carried out air strikes since Friday in the rebel-held northern half of Mali, said it planned to increase the number of its troops to 2,500.

French President Francois Hollande said he would keep French troops in Mali until the west Africa country have legitimate leaders, an electoral process and no more terrorists threatening its territory.