Malian troops headed for the remote northeastern town of Kidal on Sunday ahead of a mid-May deadline set by the government to wrest it from the control of Tuareg separatist rebels.

French forces which swept Islamist insurgents from the far north of Mali have allowed the MNLA rebels to run Kidal in recent months but Mali’s government wants to reimpose its authority ahead of July presidential and legislative elections.

The votes are intended to seal Mali’s democratic transition in the wake of a March 2012 coup triggered by a Tuareg uprising, after which al Qaeda-linked Islamists seized control of the northern two-thirds of the landlocked West African country.

A column of Malian troops left Gao, the largest city of northern Mali, for Kidal earlier this week. Defence Minister Yamoussa Camara told parliament this month that the question of MNLA control over Kidal would be resolved by May 15.

The MNLA has rejected Bamako’s calls for it to lay down its weapons, saying it would resist any Malian attempts to retake Kidal, but has said it is open to political negotiations with the government.

One military source, who asked not to be identified, said army forces had established advanced positions on the road to the small town of Anefis, 90 km (55 miles) southwest of Kidal.

The MNLA dismissed an earlier report that Malian forces had entered Anefis and said their fighters remained in control of the town.

A second army column was heading for Menaka, a town in eastern Mali close to the Niger border which was taken by the MNLA and then the Islamists last year.