MINUSMA decided to set up the zone around the town after fierce fighting between pro-government militiamen and Tuareg rebel groups left dozens dead.

The MINUSMA statement, issued Monday, called on all parties involved in the fighting "to immediately cease fighting and return to the positions they occupied before August 15, 2015".

According to the UN mission, the 20-kilometer safety zone -- which came into effect Tuesday at 8.00am GMT -- “will continue until further notice”.

It added: "Any movement inside the safe area by Platform members, or affiliated with the Platform, will be considered as an imminent danger to the security of the population of Kidal."

The "Platform" is a pro-government coalition of armed movements that includes the Gatia militia and the Tuareg-dominated Coordination of Azawad Movements (CMA).

On June 20, the Malian government and a Tuareg insurgent group, considered the country’s largest rebel organization, signed a peace deal in which the latter promised to withdraw from the town of Menaka, while armed factions associated with the Platform movement vowed to lay down their arms.

According to the MINUSMA statement, investigations will be conducted with a view to determining the groups responsible for violating the June 20 cease-fire.

Results of the investigations, it added, would be referred to the UN Security Council.

On Monday, the town of Anefif in northeastern Mali’s Kidal region reportedly fell to the pro-government Platform group.

Kidal is a stronghold for a Tuareg rebel group, which is the main component of the CMA.

The fall of Anefif on Monday was the first time since mid-2014 for the CMA to lose control of a town in the Kidal region.

In 2012, violence erupted in northern Mali following a failed coup attempt and a Tuareg rebellion that allowed al-Qaeda-linked militants to take over the northern half of the country.

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