Their foreign ministers met Friday in Niger's capital Niamey to agree on a text establishing the Confederation of the Alliance of Sahel States (AES).
"The objective was to finalize the draft text relating to the institutionalization and operationalization of the Confederation of the Alliance of Sahel States (AES)," said Niger Foreign Minister Bakary Yaou Sangare as he read the final statement late Friday.
He said the text would be adopted by the heads of state of the three countries at a summit, without specifying the date.
"We can consider very clearly, today, that the Confederation of the Alliance of Sahel States (AES) has been born," Malian Foreign Minister Abdoulaye Diop said after meeting General Abdourahamane Tiani, the head of Nigerien military regime.
The third foreign minister at the meeting was Burkina Faso's Karamoko Jean-Marie Traore.
The Sahel region has been subject to deadly jihadist violence for years, which they accused France of not being able to curb.
The three countries said late January they were quitting The Economic Community of West African States (ECOWAS), which they said was under French influence, to create their own regional grouping.