Alliance of Sahel States
At an airforce base in Bamako, Mali's army ruler General Assimi Goita presided over a ceremony marking the creation of a unified force for the Sahel countries.
The force is the latest in a series of measures by Burkina Faso, Mali and Niger to achieve closer integration.
The three countries are all led by juntas and are beset by an Islamist insurgency.
In January, Niger's defence minister said that the 5000-strong force would 'intervene together' to counter security threats in the region.
Burkinabe General Daouda Traoré was appointed to head the force which will maintain a command base in Niamey, Niger's capital.
The ceremony in Bamako was attended by the defence ministers of the Sahel Alliance member states, as well as ambassadors and representatives of international organizations accredited to Mali.
Burkina Faso, Mali and Niger formed the Sahel alliance after withdrawing from ECOWAS, which the alliance accuses of inhumane, coup-related sanctions and working against the interests of citizens in alliance countries.
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