The concept of "rule of law" in international law has not yet been clearly defined, in spite of its more frequent use in the UN official documents and the increasing interest of doctrine. Nevertheless, it is possible to distinguish the rule of law on national and international levels (the former being used interchangeably with the term Rechtsstaat or Etat de droit, the latter denotes that the international community is subjected to the rule or supremacy of international law).
During past two decades, the concept of "rule of law" in international law has evolved from political declarations to legal principles de lege ferenda and in some elements to principles de lege lata. However, it has not established in a form of general custom.
Just some elements of rule of law have become part of special treaty regimes.