Under international law, a treaty is a legally binding agreement between states (countries). A treaty can be called a convention, protocol, pact, agreement, etc. It is the content of the agreement, not its name, that makes it a treaty. Thus, the Geneva Protocol and the Biological Weapons Convention are the two treaties, although neither treaty in its name. Under U.S. law, a treaty is a legally binding agreement between countries that requires ratification and “consultation and approval” of the Senate. All other agreements (internationally treated) are called executive agreements, but are nevertheless legally binding on the United States under international law. International agreements that enter into force on a different constitutional basis from that of the Council and Senate approval are “non-treaty international agreements” and are often referred to as “executive agreements.” Congress generally requires notification when such an agreement is reached. In addition to treaties, there are other less formal international agreements. These include efforts such as the Proliferation Security Initiative (PSI) and the G7 Global Partnership Against the Proliferation of Weapons of Mass Destruction. Although the PSI has a “declaration of prohibition principles” and the G7 Global Partnership includes several statements by G7 heads of state and government, it also does not have a legally binding document that sets specific obligations and is signed or ratified by member states. Remember that there are other international agreements concluded by the United States, which are not treaty and do not require the Council and Senate approval to be binding. These agreements are generally referred to as executive agreements (see below).
“treaty,” an international agreement concluded in writing between states and governed by international law, whether inscribed in a single act or in two or more related acts, regardless of its particular name. Vienna Convention on Treaty Law, May 23, 1969, art. 2, par. 1) a), 1155 U.N.T.S. 331. International agreements are formal agreements or commitments between two or more countries. An agreement between two countries is described as “bilateral,” while an agreement between several countries is “multilateral.” Countries bound by countries bound by an international convention are generally referred to as “Parties.” If a contract does not contain provisions for other agreements or measures, only the text of the treaty is legally binding.