Confrontation of the U.S FON Program And China's Sovereign Claims in the South China Sea

South China Sea disputes among regional states have long been taken account of by the international community. China, is trying to establish its sovereignty claims over the SCS through different methods such as blocking foreign ships. But these activities have been opposed drastically by other sea powers specifically the U.S that seeks to prevent the existence of new customary rules through the FON. What is achieved in this paper can be also of use for the Islamic Republic of Iran as a target state. This paper in which an analytical-descriptive method is followed, scrutinizes the regional disputes and the relationship between PSI and the FON. It also evaluates the program as an effective mechanism for ensuring the implementation of the international law of the sea and, while introducing the US freedom of navigation program, we present our view on its legitimacy.