 Rosselli helped lead the Italian anti-fascist supporters of the republican forces, criticizing the neutrality policy of France and Britain, especially as Italy and Germany sent arms and troops in support of the rebels.In August, Rosselli and the GL organized its own brigades of volunteers to support the Spanish Republic.With Camillo Berneri, Rosselli headed the Matteotti Battalion, a mixed volunteer unit of anarchist, liberal, socialist and communist Italians.