The Vienna Convention on the Law of Treaties (VCLT) is an

international agreement A treaty is a formal, legally binding written agreement between sovereign states and/or international organizations that is governed by international law. A treaty may also be known as an international agreement, protocol, covenant, convention ...

that regulates treaties among

sovereign state A sovereign state is a State (polity), state that has the highest authority over a territory. It is commonly understood that Sovereignty#Sovereignty and independence, a sovereign state is independent. When referring to a specific polity, the ter ...

s. Known as the "treaty on treaties", the VCLT establishes comprehensive, operational guidelines, rules, and procedures for how treaties are drafted, defined, amended, and interpreted. An international treaty is a written agreement between countries subject to

international law International law, also known as public international law and the law of nations, is the set of Rule of law, rules, norms, Customary law, legal customs and standards that State (polity), states and other actors feel an obligation to, and generall ...

that stipulates their consent to the creation, alteration, or termination of their rights and obligations, as stipulated in the treaty. The Vienna Convention on the Law of Treaties was adopted and opened to signature on 23 May 1969,untreaty.un.org
''Law of treaties''
, International Law Commission, last update: 30 June 2005. Consulted on 7 December 2008.Vienna Convention on the Law of Treaties
pg. 1 became effective on 27 January 1980, and has been ratified by 116 sovereign states as of January 2018. Non-ratifying parties, such as the U.S, have recognized parts of the VCLT as a restatement of

customary international law Customary international law consists of international legal obligations arising from established or usual international practices, which are less formal customary expectations of behavior often unwritten as opposed to formal written treaties or c ...

. In treaty law, the VCLT is the authority for resolving disputes about the interpretation of a treaty.

History

The Vienna Convention on the Law of Treaties (VCLT) was drafted by the International Law Commission (ILC) of the United Nations, which began work on the convention in 1949. During the 20 years of preparation, several draft versions of the convention and commentaries were prepared by special rapporteurs of the ILC, which included prominent international law scholars James Brierly,

Hersch Lauterpacht Sir Hersch Lauterpacht (16 August 1897 – 8 May 1960) was a British international lawyer, human rights activist, and judge at the International Court of Justice. Biography Hersch Lauterpacht was born on 16 August 1897 to a Jewish family in ...

, Gerald Fitzmaurice, and Humphrey Waldock. In 1966, the ILC adopted 75 draft articles, which formed the basis for its final work. Over two sessions in 1968 and 1969, the Vienna Conference completed the convention, which was adopted on 22 May 1969 and opened for signature on the following day.

Content and effects

In the practices of international law, the Vienna Convention on the Law of Treaties is the legal authority about the formation and effects of a treaty. The legal standing of the VCLT is recognised by non-signator countries, such as the U.S. and India, as legally binding upon all sovereign states who have recognised the customary-law status of the Vienna Convention. The VCLT defines a

treaty A treaty is a formal, legally binding written agreement between sovereign states and/or international organizations that is governed by international law. A treaty may also be known as an international agreement, protocol, covenant, convention ...

as "an international agreement concluded between overeignstates in written form and governed by international law", and affirms that "every state possesses the capacity to conclude treaties." Article 1 of the VCLT restricts the application of the convention to written treaties between states, excluding treaties concluded between the states and international organizations or between international organizations. Article 11 defines "means of expressing consent to be bound by a treaty" including

ratification Ratification is a principal's legal confirmation of an act of its agent. In international law, ratification is the process by which a state declares its consent to be bound to a treaty. In the case of bilateral treaties, ratification is usuall ...

, acceptance, approval or accession. Article 26 defines ''

pacta sunt servanda ''Pacta sunt servanda'' ("agreements must be kept.") is a brocard and a fundamental principle of law which holds that treaties or contracts are binding upon the parties that entered into the treaty or contract. It is customary international law ...

'', that agreements must be kept; Article 53 defines ''jus cogens'',

peremptory norm A peremptory norm (also called ) is a fundamental principle of international law that is accepted by the international community of states as a norm from which no derogation is permitted. There is no universal agreement regarding precisely w ...

; Article 62 defines Fundamental Change of Circumstance, which determines the validity or invalidity of a treaty; and Article 77 defines

depositary In international law, a depositary is a government or organization to which a multilateral treaty is entrusted. The principal functions of a depositary are codified in Article 77 of the Vienna Convention on the Law of Treaties. Belarus The phrase ...

, the organisation or person who holds a multilateral treaty.

Scope

The Vienna Convention applies only to treaties agreed after the VCLT was ratified, and to treaties agreed between sovereign states, but does not govern other agreements between sovereign states and

international organization An international organization, also known as an intergovernmental organization or an international institution, is an organization that is established by a treaty or other type of instrument governed by international law and possesses its own le ...

s, or between international organizations, if any VCLT rules are independently binding upon such international organizations.Article 3
of the Convention. In practise, Article 2 and Article 5 of the Vienna Convention apply to treaties between sovereign states and an intergovernmental organization. However, agreements between states and international organizations or between international organizations themselves are governed by the 1986 Vienna Convention on the Law of Treaties between States and International Organizations or Between International Organizations if it enters into force. Furthermore, in treaties between states and international organizations, the terms of the Convention still apply between the state members. The Convention does not apply to unwritten agreements.

Parties to the convention

As of January 2018, there are 116 state parties that have ratified the convention, and a further 15 states have signed but have not ratified the convention. In addition, the

Republic of China Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

(Taiwan), which is currently recognized by , signed the Convention in 1970 prior to the

UN General Assembly The United Nations General Assembly (UNGA or GA; , AGNU or AG) is one of the six principal organs of the United Nations (UN), serving as its main deliberative, policymaking, and representative organ. Currently in its 79th session, its powers, ...

's 1971 vote to transfer China's seat to the

People's Republic of China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

, which subsequently acceded to the convention. There are 66

UN member states The United Nations comprise sovereign states and the world's largest intergovernmental organization. All members have equal representation in the UN General Assembly. The Charter of the United Nations defines the rules for admission of ...

that have neither signed nor ratified the convention.

Vienna formula

Signature, ratification and accession

International treaties A treaty is a formal, legally binding written agreement between sovereign states and/or international organizations that is governed by international law. A treaty may also be known as an international agreement, protocol, covenant, conventi ...

and conventions contain rules about what entities could

sign A sign is an object, quality, event, or entity whose presence or occurrence indicates the probable presence or occurrence of something else. A natural sign bears a causal relation to its object—for instance, thunder is a sign of storm, or me ...

ratify Ratification is a principal's legal confirmation of an act of its agent. In international law, ratification is the process by which a state declares its consent to be bound to a treaty. In the case of bilateral treaties, ratification is usuall ...

or accede to them. Some treaties are restricted to states that are members of the UN or parties to the Statute of the International Court of Justice. In rare cases, there is an explicit list of the entities that the treaty is restricted to. More commonly, the aim of the negotiating states (most or all of which usually end up becoming the founding signatories) is that the treaty is not restricted to particular

states State most commonly refers to: * State (polity), a centralized political organization that regulates law and society within a territory **Sovereign state, a sovereign polity in international law, commonly referred to as a country **Nation state, a ...

and so a wording like "this treaty is open for signature to ''States'' willing to accept its provisions" is used (the "all states formula"All States are defined as all UN member states and states about which there are individual statements of inclusion by the UN Secretary-General or other UN organ
Repertory of Practice of United Nations Organs Supplement No. 8; page 10UN THE WORLD TODAY (PDF)
the

United Nations Secretary-General The secretary-general of the United Nations (UNSG or UNSECGEN) is the chief administrative officer of the United Nations and head of the United Nations Secretariat, one of the United Nations System#Six principal organs, six principal organs of ...

has stated that when the "any State" or "all States" formula is adopted, he would be able to implement it only if the General Assembly provided him with the complete list of the States coming within the formula, other than those falling within the "Vienna formul
UN Office of Legal Affairs
/ref>). In the case of regional organizations, such as the

Council of Europe The Council of Europe (CoE; , CdE) is an international organisation with the goal of upholding human rights, democracy and the Law in Europe, rule of law in Europe. Founded in 1949, it is Europe's oldest intergovernmental organisation, represe ...

or the

Organization of American States The Organization of American States (OAS or OEA; ; ; ) is an international organization founded on 30 April 1948 to promote cooperation among its member states within the Americas. Headquartered in Washington, D.C., United States, the OAS is ...

, the set of negotiating states that once agreed upon may sign and ratify the treaty is usually limited to its own member states, and non-member states may accede to it later. However, sometimes a specific set of non-member states or non-state actors may be invited to join negotiations. For example, the Council of Europe invited the "non-member States"

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

, the

Holy See The Holy See (, ; ), also called the See of Rome, the Petrine See or the Apostolic See, is the central governing body of the Catholic Church and Vatican City. It encompasses the office of the pope as the Bishops in the Catholic Church, bishop ...

(

Vatican City Vatican City, officially the Vatican City State (; ), is a Landlocked country, landlocked sovereign state and city-state; it is enclaved within Rome, the capital city of Italy and Bishop of Rome, seat of the Catholic Church. It became inde ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

and the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

to "participate in the elaboration" of the 2011 Istanbul Convention and specifically allowed the

European Union The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...

(described as an "International Organisation", rather than a "State") to sign and ratify the convention, rather than accede to it, and "other non-member States" were allowed only accession. The act of signing and ratifying a treaty as a negotiating state has the same effect as the act of acceding to a treaty (or "acceding a treaty") by a state that was not involved in its negotiation. Usually, accessions occur only after the treaty has entered into force, but the UN Secretary-General has occasionally accepted accessions even before a treaty went into force. The only downside of not being a negotiating state is that one has no influence over the contents of a treaty, but one is still allowed to declare reservations concerning specific provisions of the treaty that one wishes to accede to (Article 19).

Statehood question

When a treaty is open to "States", it may be difficult or impossible for the depositary authority to determine which entities are States. If the treaty is restricted to Members of the United Nations or Parties to the Statute of the International Court of Justice, there is no ambiguity. However, a difficulty has occurred as to possible participation in treaties when entities that appeared otherwise to be States could not be admitted to the United Nations or become Parties to the Statute of the International Court of Justice because of the opposition for political reasons of a permanent member of the Security Council or have not applied for ICJ or UN membership. Since that difficulty did not arise as concerns membership in the specialized agencies, on which there is no "veto" procedure, a number of those States became members of specialized agencies and so were in essence recognized as States by the

international community The international community is a term used in geopolitics and international relations to refer to a broad group of people and governments of the world. Usage Aside from its use as a general descriptor, the term is typically used to imply the ...

. Accordingly, to allow for as wide a participation as possible, several conventions then provided that they were also open for participation to state members of specialized agencies. The type of entry-into-force clause used in the Vienna Convention on the Law of Treaties was later called the "Vienna formula", and various treaties, conventions and

organizations An organization or organisation ( Commonwealth English; see spelling differences) is an entity—such as a company, or corporation or an institution (formal organization), or an association—comprising one or more people and having a par ...

used its wording. Some treaties that use it include provisions that in addition to these States any other State invited by a specified authority or organization (commonly the

United Nations General Assembly The United Nations General Assembly (UNGA or GA; , AGNU or AG) is one of the six principal organs of the United Nations (UN), serving as its main deliberative, policymaking, and representative organ. Currently in its Seventy-ninth session of th ...

or an institution created by the treaty in question) can also participate, thus making the scope of potential signatories even broader.

Interpretation of treaties

Articles 31–33 of the VCLT entail principles for interpreting conventions, treaties, etc. These principles are recognized as representing customary international law, for example by the

International Law Commission The International Law Commission (ILC) is a body of experts responsible for helping develop and codify international law. It is composed of 34 individuals recognized for their expertise and qualifications in international law, who are elected by t ...

(ILC). The interpretational principles codified in Article 31 are to be used before applying those of Article 32, which explicitly states that it offers supplementary means of interpretation. The

European Court of Justice The European Court of Justice (ECJ), officially the Court of Justice (), is the supreme court of the European Union in matters of European Union law. As a part of the Court of Justice of the European Union, it is tasked with interpreting ...

has also applied the interpretational provisions of the VCLT in different cases, including the ''Bosphorus Queen Case'' (2018), in which the court interpreted the extent of the term "any resources" in Article 220(6) of

UNCLOS The United Nations Convention on the Law of the Sea (UNCLOS), also called the Law of the Sea Convention or the Law of the Sea Treaty, is an international treaty that establishes a legal framework for all marine and maritime activities. , 169 sov ...

. The VCLT is often relied upon in investment arbitration cases.

Footnotes

External links

Convention Text

b
Karl Zemanek
procedural history note and audiovisual material on the ''Vienna Convention on the Law of Treaties'' in th

* ttp://legal.un.org/avl/ls/Rosenboom_LT.html Lecturesb
Annebeth Rosenboom
entitled ''Practical Aspects of Treaty Law: The Depositary Functions of the Secretary-General'' and ''Practical Aspects of Treaty Law: Treaty Registration under Article 102 of the Charter of the United Nations'' (both lectures also available in French) in th

{{DEFAULTSORT:Vienna Convention on the Law of Treaties Treaties concluded in 1969 Treaties entered into force in 1980 Treaties drafted by the International Law Commission United Nations treaties Treaties of Albania Treaties of Algeria Treaties of Andorra Treaties of Argentina Treaties of Armenia Treaties of Australia Treaties of Austria Treaties of Barbados Treaties of the Byelorussian Soviet Socialist Republic Treaties of Belgium Treaties of Bosnia and Herzegovina Treaties of Brazil Treaties of the People's Republic of Bulgaria Treaties of Burkina Faso Treaties of Cameroon Treaties of Canada Treaties of the Central African Republic Treaties of Chile Treaties of the People's Republic of China Treaties of Colombia Treaties of the Republic of the Congo Treaties of Costa Rica Treaties of Croatia Treaties of Cuba Treaties of Cyprus Treaties of the Czech Republic Treaties of Czechoslovakia Treaties of Zaire Treaties of Denmark Treaties of the Dominican Republic Treaties of Ecuador Treaties of Egypt Treaties of Estonia Treaties of Finland Treaties of Gabon Treaties of Georgia (country) Treaties of West Germany Treaties of East Germany Treaties of the Kingdom of Greece Treaties of Guatemala Treaties of Guinea Treaties of Guyana Treaties of Haiti Treaties of the Holy See Treaties of Honduras Treaties of the Hungarian People's Republic Treaties of Ireland Treaties of Italy Treaties of Jamaica Treaties of Japan Treaties of Kazakhstan Treaties of Kiribati Treaties of Kuwait Treaties of Kyrgyzstan Treaties of Laos Treaties of Latvia Treaties of Lesotho Treaties of Liberia Treaties of the Libyan Arab Jamahiriya Treaties of Liechtenstein Treaties of Lithuania Treaties of Luxembourg Treaties of Malawi Treaties of Malaysia Treaties of the Maldives Treaties of Mali Treaties of Malta Treaties of Mauritius Treaties of Mexico Treaties of the Mongolian People's Republic Treaties of Montenegro Treaties of Morocco Treaties of Mozambique Treaties of Myanmar Treaties of Nauru Treaties of the Netherlands Treaties of New Zealand Treaties of Niger Treaties of Nigeria Treaties of Oman Treaties of Palestine Treaties of Panama Treaties of Paraguay Treaties of Peru Treaties of the Philippines Treaties of Poland Treaties of Portugal Treaties of South Korea Treaties of Moldova Treaties of the Soviet Union Treaties of Rwanda Treaties of Saudi Arabia Treaties of Senegal Treaties of Serbia and Montenegro Treaties of Slovakia Treaties of Slovenia Treaties of the Solomon Islands Treaties of Francoist Spain Treaties of Saint Vincent and the Grenadines Treaties of the Republic of the Sudan (1985–2011) Treaties of Suriname Treaties of Sweden Treaties of Switzerland Treaties of Syria Treaties of Tajikistan Treaties of North Macedonia Treaties of Timor-Leste Treaties of Togo Treaties of Tunisia Treaties of Turkmenistan Treaties of the Ukrainian Soviet Socialist Republic Treaties of the United Kingdom Treaties of Tanzania Treaties of Ukraine Treaties of Uruguay Treaties of Uzbekistan Treaties of Vietnam Treaties of Yugoslavia 1969 in Austria Treaty law treaties Treaties extended to the Faroe Islands Treaties extended to Greenland Treaties extended to the Netherlands Antilles Treaties extended to Aruba Treaties extended to West Berlin May 1969 1960s in Vienna