BAMAKO, Mali — President Emmanuel Macron of France on Sunday promised strong support for a new multinational military force to combat extremists in parts of West Africa, saying the “terrorists, thugs and assassins” needed to be eradicated.

Meeting in Mali with leaders from the five countries that make up the Sahel region, Mr. Macron said France would provide military support for antiterrorism operations and 70 tactical vehicles, communications, and operational and protective equipment.

The 5,000-strong force will be deployed by September, Mr. Macron said at a news conference in the Malian capital, Bamako, by which time the force’s funding is expected to be finalized.

The leaders of Mali, Mauritania, Niger, Burkina Faso and Chad — the countries of the Sahel region known as the G5 — must clarify their roles and contributions for the force to attract more support from outside countries, Mr. Macron added. “We cannot hide behind words, and must take actions,” he said.