The Vienna Convention on the Law of 358 A172379801.1 Treaties states that a "reservation" is not valid if it "is incompatible with the object and purpose of the treaty." Vienna Convention on the Law of Treaties, Jan. 27, 1980, 1155 U.N.T.S. 331, art. 19(c); see also Restatement (Third) of Foreign Relations Law of the United States, § 313(1)(c) (1987) ("A state may enter a reservation to a multilateral international agreement unless the reservation is incompatible with the object and purpose of the agreement."). This rule of international law has been adopted by the International Court of Justice and the United Nations General Assembly.