Fishermen tidy up their nets at Hagu Teungah beach, in Lhokseumawe

Fishermen tidy up their nets at Hagu Teungah beach, in Lhokseumawe. For Indonesia, the marine environment affects the livelihood of its coastal communities. UNCLOS is pivotal for its protection. (Photo: AZWAR IPANK / AFP)

Why UNCLOS Matters

Sovereignty, Security and Prosperity: Indonesia and the UN Convention on the Law of the Sea


The passage of UNCLOS (1982) was a diplomatic and existential success story for Indonesia, the world’s largest archipelagic state. However, new challenges in maritime law have arisen in the 40 years since the Convention’s passage and action must be taken to ensure its continued relevance to Indonesia and the world.

Editor’s Note:

This article is part of “UNCLOS 40th Anniversary Series – Why UNCLOS Matters” conceptualised by the Blue Security programme. The series, which commemorates the 40th anniversary of the UN Convention on the Law of the Sea, brings together established and emerging maritime security scholars from Southeast Asia and the broader Indo-Pacific to address the pertinence and relevance of UNCLOS. Blue Security brings together Australian and Southeast Asian experts to look at a range of maritime security issues across the region. The series was developed by Dr Troy Lee-Brown and Dr Bec Strating. It is published in collaboration with the team at Fulcrum.

The United Nations Convention on the Law of the Sea (UNCLOS) is important for Indonesia. Consisting of more than 17,000 islands, Indonesia has historically struggled to govern its expansive archipelago. Global recognition for its archipelagic status was important for Indonesia from the early days of its independence and the negotiation of UNCLOS is a vindication of Indonesia’s position. The international law of the sea will become even more important in the future for Indonesia.

In the early years after Independence, then Indonesian Prime Minister Djuanda Kartawidjaja held concerns that foreign warships and other vessels could freely transit through Indonesia’s littoral waters. He argued that this could pose a serious threat to Indonesia’s national security and introduced the Djuanda Declaration in 1957. In the Declaration, Indonesia unilaterally claimed that the maritime areas surrounding the archipelago should be recognised as being under Indonesia’s sovereignty and, therefore, closed to international navigation. Despite protests from the international community, Indonesia enacted the declaration as its national law in 1960. This position became Indonesia’s starting point for its campaign to be recognised as an archipelagic state during the long negotiation for UNCLOS to become reality.

After more than 30 years of negotiations at various international conferences, Indonesia was finally recognised as an archipelagic state under international law. Indonesia’s territory essentially doubled, from 2,027,087 km² to 5,193,250 km². The inclusion of the provisions and principles governing archipelagic states within UNCLOS is regarded as one of Indonesia’s greatest diplomatic successes. Looking ahead, there are three main reasons why UNCLOS will become more important for Indonesia going forward.

First, maritime security has become more complex compared to when UNCLOS was negotiated in the 1970s and 1980s. Technology has become more advanced and transnational issues such as human trafficking, armed sea robbery, piracy, and ‘illegal, unreported and unregulated’ (IUU) fishing activities are complex problems requiring international coordination. UNCLOS has already established some important principles, such as universal jurisdiction to tackle piracy on the high seas. Indonesia will have to step up its responses to transnational crime at sea, including increasing cooperation with regional neighbours to tackle piracy and other issues.

Second, UNCLOS is pivotal in the protection of the regional marine environment. For Indonesia, the marine environment affects the livelihood of its coastal communities, particularly given challenges like marine plastic and rising sea levels. With the increasing threat of climate change, conserving the ocean environment has become even more important. UNCLOS’ principles and obligations for all parties to protect and preserve the marine environment are beneficial to the Indonesian archipelago.

People protest against China’s claims on the disputed South China Sea, outside the Chinese Embassy in Jakarta on December 8, 2021. (Photo: Dasril Roszandi / AFP)

Third, Indonesia’s rights as an archipelagic state under UNCLOS allow it to explore and exploit its marine resources within its exclusive economic zone (EEZ) and on its continental shelf. To protect Indonesia’s marine resources, President Joko Widodo’s administration has strongly implemented the ‘sinking vessels policy’ to combat IUU practices. While the burning and sinking of foreign vessels is not specifically mentioned in Article 73(1) of UNCLOS, Indonesia views itself as entitled to take “necessary” measures to ensure compliance with its laws. Despite these measures being controversial, Indonesia believes they are helping to effectively eradicate IUU fishing in its EEZ and beyond.

As an archipelagic state, Indonesia under UNCLOS’ Article 53 can designate archipelagic sea lanes passages and is the only country that has done so, albeit partially. Indonesia has not yet designated the East-West route for international navigation. Archipelagic sea lanes are important as they assign designated lanes to foreign vessels when entering Indonesian archipelagic waters.

Other challenges such as preserving and allowing equal access to biodiversity beyond national jurisdictions remain.

Despite UNCLOS’s many benefits for Indonesia, there are some challenges that the Convention does not cover, such as those relating to emerging technologies like unmanned underwater vehicles (UUV). In the last two years, at least five UUVs have been found in Indonesian archipelagic waters, mostly Chinese research UUVs. The unclear status of such vehicles under international law is problematic for Indonesia. At minimum, the question of whether UUVs are “warships” mentioned in UNCLOS’ Article 29 would have to be resolved.

Other challenges such as preserving and allowing equal access to biodiversity beyond national jurisdictions remain. Currently, the international community is negotiating terms on Marine Biodiversity Beyond National Jurisdiction (i.e., the ‘BBNJ treaty’), which will fall under UNCLOS’s auspices and deals with biodiversity beyond coastal states’ jurisdiction. Indonesia has actively participated in the treaty negotiations and will be interested in ensuring its equitable access to all the benefits of marine biodiversity.

The historic passage of UNCLOS in 1982 conferred upon Indonesia its status as an archipelagic state. It is in its national interest that UNCLOS be respected and complied with internationally. As a responsible maritime nation-state, Indonesia can help to address the complex challenges facing the international community by ensuring UNCLOS’ continued relevance.


This article is part of the ‘Blue Security’ project led by La Trobe Asia, University of Western Australia Defence and Security Institute, Griffith Asia Institute, UNSW Canberra and the Asia-Pacific Development, Diplomacy and Defence Dialogue (AP4D). Views expressed are solely of its author/s and not representative of the Maritime Exchange, the Australian Government, or collaboration partner country government.

Aristyo Rizka Darmawan is a Lecturer in International Law and researcher at the Centre for Sustainable Ocean Policy at Universitas Indonesia.