How Uti Possidetis Juris Made West Papua a Part of Indonesia

Indonesia went through a great length to reclaim West Papua Province after the country’s independence. Diplomatic and military operations were launched, including the Trikora Operation that claimed the life of Commodore Yos Sudarso. While many still contest Indonesia’s claim of West Papua, the decision was supported by a legal principle called Uti Possidetis Juris.

Definition of Uti Possidetis Juris


Yuri Octavian Thamrin, the Ambassador of Indonesia for EU, Belgium, and Luxembourg, stated in a 2016 public class in Universitas Indonesia that he always uses Uti Possidetis Juris as the main argument to address West Papua’s status. Uti Possidetis Juris came from a Latin expression that basically means, “you keep what you once possessed.” It means that certain territory with all its properties must stay with the possessor after war or conflict.

The term was first coined by King James I of England in the 17th century, following disputes with the Kingdom of Spain about the occupied Western Hemisphere regions. The principle was later used as the undisputed international law aspect, applied after conflicts, wars of independence, and the falls of dictatorship or monarchy. It still applied during the Europeans’ withdrawal from Asian and African countries.

When Indonesia declared independence in 1945, all the areas formerly occupied by Netherland were back to the Indonesian government. Uti Possidetis Juris principle thus stated that, since West Papua was occupied by the Netherland and included in the East Indie map, the province automatically became the part of Indonesia.

The Affirmation and Position of Uti Possidetis Juris


Uti Possidetis Juris has been formally accepted by countries around the world as a solution after conflicts or other exceptional situations, except there are treaties or agreements that say otherwise. When Indonesia’s founding fathers discussed the geographical aspects of the new country, this principle was used to include West Papua into one of the priorities after the declaration.

Muhammad Hatta, one of the founding fathers and the first vice president of Indonesia, stated that Indonesia’s official regions would include West Papua. Not only it followed the Uti Possidetis, but it also deflected the wilder claim by Muhammad Yamin, who said that Indonesia’s regions must extend to Thailand based on the map of Majapahit Kingdom.

Since the Netherland Kingdom formally claimed West Papua when extending the queen’s reach to Indonesia, this province automatically became the part of newly-formed, independent Indonesia. Therefore, any claims Netherland had made after Indonesia’s declaration of independence were not valid. West Papua has automatically become a part of Indonesia since the beginning.

Uti Possidetis Juris and Right to Self-Determination


The right to self-determination, which defines the right for a colony or disputed region to determine its own right, often becomes the main reason to debate the fact that West Papua belongs to Indonesia. However, the right to self-determination is universally acknowledged as a one-time notion.

Indonesia’s right to self-determination has been established on 17 August 1945, when the country declared its independence. By following Uti Possidetis, it means that West Papua was included in it. An established country cannot be broken up, and countries that have acknowledged the sovereignty must also accept it.

Some people debate the application of Uti Possidetis, and claim that it can be broken if the region is oppressed. However, despite all the typical problems in the region, Indonesia is still committed to providing equal services to Papuans. President Joko Widodo has created various programs to improve various important aspects in Papua, from building infrastructures to reducing the cost of fuel. This proves Indonesia’s commitment, and support the Uti Possidetis claim regarding of West Papua.

International Responses toward Indonesia and West Papua Status


Various countries have shown support for Indonesia in reclaiming West Papua, even from the early years after independence. The United States shifted its stance from neutral to supporting Indonesia in diplomatic and military operations, proven by the country’s willingness to sell weapons and military vehicles to Indonesia. The US also influenced United Nations to mediate the process, speeding up West Papua’s return to Indonesia.

Iran and Pakistan were also among the first countries that showed support in Indonesia’s missions to reclaim West Papua. After the military operations, shortly before Indonesia held the Act of Free Choice, Jalal Abdoh from Iran led the United Nations Temporary Executive Authority. UNTEA served as the temporary holder of authority in West Papua until Indonesia and Netherland Kingdom settled the matter. General Brigadier Said Uddin Khan from Pakistan led UNSF, the UN’s security forces tasked to keep the peace during the process.

When Indonesia finally sent representatives to PEPERA (The Act of Final Choice), who voted for West Papua to return to Indonesia, the result was acknowledged by the UN delegations.



Uti Possidetis Juris is one of the formally acknowledged and respected legal principles in the world, and it has worked wonderfully in mediation efforts after conflicts and wars. Indonesia has always had a legal claim for West Papua. With this legal principle as the basis, there should be no reason why West Papua cannot stay as an integral part of Indonesia.