In order to prevent the consolidation of de facto authorities established in a territory following an unlawful use of force and/to contempt of rights of the involved peoples to self-determination, international law imposes obligations to third States.  Treaties entered into with the de facto authorities established on such territories on matters concerning them must ensure the interests of the people under their jurisdiction. Otherwise, these states must expect that these treaty relations will be criticized and eventually be denounced by international and national courts. Of the same concern is the origin of the distinction that international law establishes between the different acts of the de facto authorities administering these territories . Administrative acts issued to safeguard the civil rights of the people within their jurisdiction will not be null and void unlike those that seek to allow the population to enjoy the benefits of international cooperation. This is difficult distinction to establish and implement.