• Legis Scriptor

An Introduction of Treaties under International Law

Authored by Triyasa Gope

Keywords:- Treaties, International Law, United Nations


Treaty, a significant part of international law. The concept of the treaty changed with time. In ancient times treaties were used to be in oral form. They took oath in the name of God and then treaties were worked as a binding force in the society. But now, treaties must be in a written form and legally binding to the parties. In this article treaty as a source of international law, the second part describes treaties as a law of the land, third types of treaties, fourth is the termination of a treaty, and last but least conclusion of the article.


Treaties are a very important source of Public International Law. According to Duhaime's law dictionary, a treaty means a formal agreement between two states signed by official representatives of two states.[i] The rules of treaties between two states are in the Vienna Convention on Law of Treaties, 1969, and rules of treaties between States and international organizations materialize in the Vienna Convention on the Treaties Between States and International Organization or Between International Organizations, 1986.

According to Article 1 of the 1969 Vienna Convention On Law Of Treaties, "Treaty means an international agreement concluded between States in written form and governed by international law, whether embodies in a single instrument or in two or more instruments and whatever its particular designation."[ii] A treaty can be created on anything which might create disputes and unevenness among the parties of the treaty.

Treaties are like contracts. There are proposals and acceptance like a contract. That's why the initial stage of a treaty is also an agreement like a contract. The agreement comprises certain points for the benefit of all the parties, the rights and, duties, and terms, and conditions on which all the participants should acknowledge mutually. The agreement is enforceable by law. The agreement governs the law related to it but it depends on its enforceability. Treaties are made with a set of agreements.

So when the states enter into a treaty they have to follow their responsibilities and those are binding in nature by international law. The guidelines on the treaty and enforcement of them are discussed in the Vienna Convention on Law of Treaties. Treaties are described in international law. Treaties are expected to be performed faithfully keeping in mind 'Pacta Sunt Survanda' (agreements must be kept), the soul principle of international law.

Treaties are always written. If there is any implied treaty, they are not enforceable by law.

Treaties as a Source of International Law

Treaties are known as a primary source of international law. Making of treaties is an important method of formulating international law. Making international law through treaties is the most popular method of formulating international law. When two states enter into a treaty the rights, and responsibilities of that treaty become law on those particular states.

Treaties like The 1919 Treaties of Versailles and the 1945 UN Charter established new rules in international law, especially where there need to respond very instantly with changing circumstances. Because many treaties took too much time to negotiate especially environmental treaties like the Geneva Convention on Long-Range Transboundary Air Pollution (1979), the Kyoto Protocol (1997), etc.

The primary sources of international law are:-

• Treaties and conventions

• Judicial works

• Precedents

• Custom

• General principles of law.

Treaties are guaranteed international security, community, and peace. This is one of the reasons treaties are regarded as fundamental sources of international law.

Treaties as a Land of Law (U.S. Constitution):- In the United States treaties are treated as a land of law. Article six of the U.S. Constitution consists that treaties are law of the land. Treaties that do not expire with time are enforced as a law of land like the constitution and bill of rights. For example, treaties between Indian tribes, and the United States government. It is also treated as law of the land.

In the case of Foster vs Neilson,[1] chief justice of the Supreme Court of the United States Justice Marshall described that a treaty is to be considered "as equivalent to an act of the legislature, whenever it operates of itself, without the aid of any legislative provision."

But these days Courts find many obstacles to the enforcement of treaties as a law of the land because the parties of the treaties made the same for their benefits rather than domestic adjudication. The enforcement of treaties now is in difficulty. But the Constitution of the United States declared treaty as a law of the land and judges are bound to do that. The diplomats who made the Constitution knew that treaties are made for the personal interest of the parties, but they were done this because they wanted to avoid international conflicts and to avoid the results of a violation of treaties.

Types of Treaties

There are two types of treaties. These are-

• Bilateral Treaty,

• Multilateral Treaty.

Bilateral Treaty:- Bilateral treaties are done between the two countries, and the obligations are also followed by two entities. For example, a treaty between India and South Korea is a bilateral treaty. It is important to note there is no necessity to have only two parties. In bilateral treaties, there may be more than two parties, but there should have only two states. For example, a treaty between India and the European Union, and it's 17 states. In this treaty, all the rights, and obligations are on two parties, i.e. India and the EU. Any obligation would not rise between the EU and its members.

Multilateral Treaty:- Multilateral treaty means a pact between three or more parties. These might be international or domestic. The rights and obligations arise among all the parties. That means each participant has an obligation over other participants.

Treaties with a higher number of participants gain much value on the international platform. It shows how important the issue of the treaty is. But sometimes the issue of bilateral treaties are also significant. For example, issues like arms limitation, atomic arms prohibition, terrorist control, etc.

Termination of Treaty:-

• Withdrawal:- Obligations of the treaty arises with the approval of all the parties. For that reason, treaties are mostly not binding in nature. Any party can withdraw the treaty with the consent of other parties.

Article 56 of the Vienna Convention on Law of Treaty deals with the withdrawal of treaties that do not have any provision of withdrawal, termination, and denunciation. According to this article, when a treaty is subject to denunciation -

- The intention of parties to admit the possibility of withdrawal was established.

- The right of withdrawal should be implied like the treaty.

• Termination and Suspension:-

1. Implied by the conclusion of a later treaty:- When the same parties make another treaty in the identical subject matter then the previous equivalent shall be deemed to be terminated. Now the new treaty's provisions govern the parties and parties are also intended to follow that. If two treaties provisions are so contrary to each other that two treaties are impossible to impose at the same time, then the first treaty will terminate if there is an implied intention to do that by the parties.

2. As a consequence of its breach:- If one party breaches the treaty there are different consequences for different kinds of treaties. If the treaty is bilateral and one of the parties done material breach of the treaty then the other party can terminate the treaty at that period. On the other hand, if the treaty is multilateral then default by any party authorizes other parties to terminate a treaty wholly or partially.

3. Impossibility of performance:- The impossibility of performing the obligations of the treaty is a sufficient ground for termination of a treaty. If the impossibility is permanent then the treaty will be terminated and if the impossibility is temporary then the provisions of the treaty will be stuck down for that period.

If the impossibility is happening because of any part of that treaty, then the treaty may not be terminated.

Conclusion:- Treaties may be defined as an agreement between parties where their rights and responsibilities are written and follow a set of rules. It is also known as pacts, agreement, charters, etc. There have many types of treaties, and they are divided based on the object. Like there are Political treaties, commercial treaties, crime treaties, constitutional treaty, etc. Vienna Convention on Law of Treaties provides basic principles to govern the treaties. There are many clauses related to the definition of treaty, termination, withdrawal of a treaty, etc.

Treaty plays a vital role in international law and maintains a good relationship between States for world peace.

Foot notes:

[1] Foster vs. Neilson, 27 U.S. (2 Pet.) 253 (1829) [i] Duhaime’s Law Dictionary, ( <,and%20whatever%20its%20particular%20designation.%22&text=%22A%20treaty%20is%20in%20the, of%20a%20contract%20between%20nations.%22> accessed 17 September 2020 [ii] Ibid