French troops have arrived in the last of three major northern Mali towns where Islamist rebels ousted government forces last year.
A French military spokesman confirmed that "French elements were put in place last night in Kidal", which is situated near the border with Algeria.
He declined to give details of the operation, which comes two days after French and Malian forces liberated the historic town of Timbuktu from the al-Qaeda-affiliated militants. Before that they freed the town of Gao.
France Info radio reported that a French military aircraft had landed at Kidal airport.
Kidal is a stronghold of homegrown Islamist group Ansar Dine, which is led by a former Tuareg independence fighter Iyad ag Ghali. It was unclear however whether his forces still controlled the town.
A splinter group and a secular Tuareg independence movement have both claimed to have taken control there in recent days.