Mali, Niger and Burkina Faso, three West African Sahel nations ruled by military juntas, signed a security pact on Saturday promising to come to the aid of each other in case of any rebellion or external aggression.

The three countries are struggling to contain Islamic insurgents linked to al Qaeda and Islamic State and have also seen their relations with neighbours and international partners strained because of the coups.

The latest coup in Niger drove a further wedge between the three and countries of the regional bloc, the Economic Community of West African States, which has threatened to use force to restore constitutional rule in the country.

Mali and Burkina Faso have vowed to come to Niger’s aid if it is attacked.