The legitimacy issue of unilateral economic measuresinter national law

The increasing tendency of states to resort to unilateral economic measures without referring to the relevant international organizations as a means to achieve various objectives has made this issue one of the controversial topics in the field of international studies. Although these measures do not involve military force, their legal and humanitarian impacts raise important questions about their legitimacy. This study aims to analyze the legitimacy of unilateral economic measures in international law, both within and outside treaty relationships. The first section addresses the concept of unilateral economic measures, examines their historical development, distinguishes them from similar concepts, and classifies their types. The second section evaluates the sources of legitimacy of these measures from three perspectives: First, the principle of exceptio non adimpleti contractus is examined within the framework of treaty relationships as a form of countermeasure applicable when the other party breaches its obligations. Different doctrinal views are discussed, with preference given to the opinion that considers it a countermeasure. Second, countermeasures outside treaty relationships are analyzed in the context of states' international responsibility. This includes unilateral economic measures applied as responses to non-contractual breaches. Third, the use of unilateral economic measures as tools of political or economic coercion, especially without collective authorization by the international community, is explored, along with the related legal challenges. This study seeks to provide a balanced legal perspective on the legitimacy of unilateral