International Agreements: A Focus on Entry and Exit Clauses 

by Chiara Fiorino

Treaties are the backbone of international law. Even though treaties can be called many different things such as a Convention, an Accord, a Protocol, a Pact, etc., they are considered to be binding agreements between two or more countries according to the Vienna Convention (Article 26) [1].  Treaties are usually created to govern the relationships between States on a wide range of topics, such as nuclear weapons, trade, environment, human rights, and terrorism – to just name a few. But what are the rules that govern treaties themselves? 

The Vienna Convention on the Law of Treaties, which was adopted in 1969, is an international agreement that contains the rules intended to govern how treaties are drafted, established, revised, and operated by its signatory countries – which are called Parties after officially joining an agreement [1]. Specifically, this article will dive into the rules that allow countries to enter and exit international agreements. 

How to Become a Party to an International Agreement 

A simple signature is not sufficient for States to become part of an international agreement. Indeed, signatures only authenticate the final text, and symbolize the willingness to join such agreement in the coming future. On the contrary, States officially become Parties to an agreement after they submit a ratification, acceptance or approval act that expresses their consent to be legally bound to the treaty’s obligations, duties, and rights [2]. The entry process varies according to the national laws and ratification procedures of each country [3]. For instance, approval and acceptance instruments are used in lieu of ratification when the treaty does not need to be endorsed by the head of state [2].

If a treaty has already entered into force, it is still possible for countries to become a Party to it. In this case, States will submit an accession act, which has the same legal effects as the aforementioned instruments [2].

The Different Ways to Exit an International Agreement

Although a treaty is binding, it usually contains exit clauses that allow States to potentially withdraw from it. The withdrawal process varies depending on the specific terms of each treaty. 

A Focus on the Paris Agreement

There was significant debate surrounding the binding nature of the Paris Agreement during the drafting process. For example, in the United States (US) to make the Paris Agreement itself, its obligations and goals, compulsory it would have had to pass successfully through the then Republican-controlled Senate, which all but doomed to fail [4]. So instead, it was agreed that while the required processes would be legally binding (such as submitting Nationally Determined Contributions (NDCs) every five years and attending Conferences of the Parties), obligations under the Paris Agreement would not be binding [4]. Therefore, as long as countries do submit NDCs these can be progressive or regressive without any consequences. 

Entry and Exit from the Paris Agreement

Article 28, comma 1 (section of the agreement) enables Parties to give notice of withdrawal no earlier than three years after entry into force in the respective country [5]. Article 28, comma 2 further specifies that the notification of withdrawal takes one year to become effective [5]. Therefore, the Paris Agreement has a maximum of a four- and a minimum of a one-year exit process. 

For example, although former US President Trump said already in 2016 that he wanted to leave the Paris Agreement, his administration had to wait until November 4, 2019 to submit the official notice of withdrawal [6]. The US officially ceased to be part of the Paris Agreement only one year later, in 2020. It is important to note, however, that during this four-year process the US was still required to respect the legally binding processes under the Agreement [7].

Additionally, when a country leaves an international agreement, there are no rules that forbid its re-admission. Indeed, President Biden decided to rejoin the climate agreement and  since February 19, 2021 the US is now again a Party to it [8].

Another way to exit an agreement or protocol is to withdraw from the overall Convention that established such treaties. For instance, Parties can withdraw from the Paris Agreement by withdrawing from the United Nations Framework Convention on Climate Change (UNFCCC) itself [4]. Similarly, Parties can pull out from the Cartagena Protocol and/or Nagoya Protocol by leaving the Convention on Biological Diversity (CBD), as per its Article 38 [9]. As of today, however, no country has ever excited the above Conventions.  

Reference List

[1] United Nations, 1969,  Vienna Convention on the Law of Treaties. Signe 23 May 1969. Entered into force 27 January 1980. United Nations, Treaty Series, vol. 1155, p. 331. Retrieved from: [Accessed 1 Dec. 2021]

[2] United Nations Treaty Collection (UNTC). Glossary of terms relating to Treaty actions. Treaty section, Office of Legal Affairs, New York. Retrieved from: [Accessed 1 Dec. 2021]

[3] Science Safety and Security, 2018, International Agreements. Retrieved from: [Accessed 6 Dec. 2021]

[4] Keating J., 2015, The One Word That Almost Scuttled the Climate Deal, Slate, Retrieved from: [Accessed 4 Jan. 2022]

[5] United Nations, 2015, Paris Agreement. Retrieved from: [Accessed 30 Nov. 2021]

[6] Hollis D., 2017, What to look for in any U.S. withdrawal from the Paris Agreement. OpinioJuris. Retrieved from: [Accessed 30 Nov. 2021]

[7] Tabuchi H. & Fountain H., 2017. Bucking Trump, These Cities, States and Companies Commit to the Paris Accord. The New York Times. Retrieved from: [Accessed 30 Nov. 2021]

[8] Blinken A. (US Secretary of State), 2021. The United States Officially Rejoins the Paris Agreement. U.S. Department of State. Press Statement. Retrieved from: [Accessed 6 Dec. 2021]. 

[9] United Nations, 1992. Convention on Biological Diversity. Retrieved from: [Accessed 30 Nov. 2021]

Categories COP26

Tell us what you think!

This site uses Akismet to reduce spam. Learn how your comment data is processed.