Delimitation of maritime zones between Greece and Turkey

Binias, Eleftherios; Μπίνιας, Ελευθέριος

Master Thesis

Author

Binias, Eleftherios

Μπίνιας, Ελευθέριος

Date

2025

Abstract

My thesis examines the complex and crucial question of the delimitation of maritime zones between Greece and Türkiye through the lenses of public international law, the law of the sea, international jurisprudence, and geopolitics. The delimitation of maritime zones is vital, as it affects political stability, economic development, and the exploitation of the natural resources of coastal states. Clear boundaries reduce the risk of conflict, strengthen bilateral and multilateral relations, and provide legal certainty for economic activity such as fishing, hydrocarbon exploration and production, and maritime transport. Starting from the historical context, the bilateral disputes stem primarily from the Treaty of Lausanne of 1923, which laid the initial foundations for today’s claims. The most intense period began in the 1970s with the discovery of potential hydrocarbon deposits in the Aegean. In 1973 Türkiye issued unilateral exploration licenses, prompting an immediate reaction from Greece and a diplomatic crisis. The 1974 crisis in Cyprus was a turning point, with Türkiye invading and occupying the northern part of the island. This action had significant geopolitical repercussions and further strained Greek-Turkish relations. In 1976 a new crisis arose when Türkiye conducted surveys in the Aegean, leading Greece to request provisional measures from the International Court of Justice. The Court held that without a prior delimitation, immediate harm could not be established. The Aegean crisis of 1987 marked another peak of tension, as Türkiye attempted new surveys in areas of disputed continental shelf, bringing the two countries to the brink of military confrontation. In 1996 the Imia crisis again highlighted the need for delimitation based on international law. The recent crisis of 2020, triggered by surveys carried out by the research vessel Oruç Reis on the Greek continental shelf, brought the issue back to the forefront and underscored the urgency of a final settlement. More recently, the submission of conflicting maps to the United Nations by Greece and Türkiye in 2025 shows that the dispute remains active and requires a legal and peaceful resolution. Today the Eastern Mediterranean is marked by heightened tension, amplified by political and military activity on both sides. The absence of an agreed delimitation creates uncertainty, hinders economic development, and increases the risk of conflict. A stable and clear delimitation through the International Court of Justice would significantly ease these challenges. The Eastern Mediterranean has also drawn international attention due to recently identified energy deposits. Beyond their economic value, these discoveries have changed the geopolitical balance and intensified competing claims by states, including Greece and Türkiye. A clear legal delimitation is therefore a prerequisite for the peaceful exploitation of these resources. Under the 1982 United Nations Convention on the Law of the Sea, the territorial sea extends up to twelve nautical miles and is an area of full sovereignty. By contrast, the exclusive economic zone and the continental shelf confer specific sovereign rights for the exploration and exploitation of natural resources, without full sovereignty. In these zones the coastal state cannot prohibit freedom of navigation or other activities unrelated to natural resources. The continental shelf exists ipso facto and ab initio and does not require proclamation, while the exclusive economic zone must be expressly declared. The continental shelf concerns the seabed and subsoil, whereas the exclusive economic zone also confers rights in the water column, including fishing, energy resources, and research. Understanding this distinction is essential, as it shapes the claims and strategies of the states involved, especially in the Eastern Mediterranean where interests overlap. UNCLOS provides the main legal framework for delimitation. Articles 74 and 83 stress negotiation in good faith and the avoidance of unilateral actions that could worsen the situation, with the aim of reaching an equitable result. Article 15 sets the median line as the basic method for delimiting the territorial sea, while recognizing that special circumstances, such as the presence of islands or markedly uneven coasts, may justify adjustments. In the Aegean, with its many islands, both the median line and special circumstances acquire particular importance. Article 121 clarifies the rights of islands. Islands capable of sustaining human habitation and economic life are entitled to a territorial sea, continental shelf, and exclusive economic zone. Rocks that cannot sustain such habitation or economic life do not automatically generate full maritime zones. This article is central to the competing claims of Greece and Türkiye. In delimitation, tribunals consider the configuration of coasts, the length of coastlines, the presence and effect of islands, and the principle of proportionality. The distinction between sovereignty and sovereign rights is also critical. Sovereignty applies fully within the territorial sea, while sovereign rights concern the resources of the continental shelf and the exclusive economic zone. Selected cases illustrate how international courts apply these principles. In Bangladesh v. Myanmar (2012), the International Tribunal for the Law of the Sea held that islands that would distort the delimitation should not receive full effect. The tribunal began with a provisional equidistance line and then adjusted it to achieve a more equitable and proportionate outcome, limiting the effect of St Martin’s Island despite its habitation. In Romania v. Ukraine (2009), the International Court of Justice significantly reduced the effect of Snake Island, given its limited geographic and economic significance, to avoid a disproportionate result in the Black Sea. In Nicaragua v. Colombia (2012), the Court emphasized avoiding the enclaving of islands and granted small Colombian features only limited maritime zones to preserve a fair balance. These precedents are instructive for the Aegean, where the effect of islands depends on their position and on the overall proportionality of the result. In conclusion, the most effective and fair solution is referral to the International Court of Justice or to the International Tribunal for the Law of the Sea, which can provide transparency, justice, and stability for the region.

Postgraduate Studies Programme

Energy: Strategy, Law & Economics

Department

Σχολή Οικονομικών, Επιχειρηματικών και Διεθνών Σπουδών. Τμήμα Διεθνών και Ευρωπαϊκών Σπουδών

Number of pages

Language

English

URI

https://dione.lib.unipi.gr/xmlui/handle/unipi/18284

Collections

Τμήμα Διεθνών και Ευρωπαϊκών Σπουδών

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Except where otherwise noted, this item's license is described as
Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ελλάδα