The File Opened in 2025: Türkiye's Marine Spatial Planning and the IOC-UNESCO Registration

Why It Matters

On 16 April 2025 Türkiye unveiled its Marine Spatial Planning of the Republic of Türkiye (Türkiye Cumhuriyeti Deniz Mekânsal Planlaması), and on 12 June 2025 it was officially recorded with the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO). According to Ankara, this was the first time Türkiye's positions across the Black Sea, the Aegean Sea and the Mediterranean were placed on record with a United Nations body.

The step matters because maritime claims are usually argued through ship movements and press statements, while this one was lodged in a scientific, document-based channel. It does not settle any boundary, but it adds a dated, verifiable file to the chain of Turkish filings that began in 2004. This guide sets out what was registered, where it sits in that chain, what Athens and Nicosia say in response, and why the story travelled so little.

Background

The geography and the historical claim

Türkiye has a mainland coastline of about 870 km (roughly 540 miles) on the Eastern Mediterranean, the longest of any state on that sea's mainland shores. Turkish official narrative links this to a long naval and commercial presence in the basin, symbolised by the 1538 Battle of Preveza, when an Ottoman fleet defeated a Holy League fleet and Ottoman naval primacy in the Mediterranean followed for decades (often called Pax Ottomana). Historical memory is not a legal title, and the file does not treat it as one. Ankara uses it to explain why the coastline, not a historical claim, is the starting point for its legal argument.

The central geographic fact of the dispute is that a long mainland coast faces a cluster of Greek islands (Kastellorizo/Meis, Rhodes, Karpathos, Crete) lying very close to it, and the island of Cyprus to the south. How much maritime space those islands generate, compared with the mainland coast, is the core of the disagreement.

Why equity is the legal fulcrum

Delimitation of the continental shelf and exclusive economic zone (EEZ) between states with opposite or adjacent coasts is, under customary international law, meant to reach an equitable solution. Article 83 of the 1982 UN Convention on the Law of the Sea (UNCLOS) uses that wording. Türkiye is not a party to UNCLOS, and says so openly, but it relies on the equity principle as it developed in case law:

• North Sea Continental Shelf cases (ICJ, 1969): rejected a rigid equidistance rule as mandatory and emphasised equitable principles.
• Anglo-French Arbitration (1977): gave the Channel Islands, lying close to the French coast, a limited enclaving treatment rather than full effect.
• Libya/Malta (ICJ, 1985): disregarded the small islet of Filfla in drawing the boundary.
• Romania v. Ukraine (ICJ, 2009): gave no weight to Serpents' Island in the delimitation line.

Ankara reads this body of decisions as confirming that small islands near a long mainland coast do not automatically cut off that coast's projection. Greece reads UNCLOS Article 121 as giving inhabited islands the same entitlements as other land territory. That difference of reading is the legal heart of the file.

The chain of filings before 2025

The 2025 recording is easier to understand as the latest entry in a sequence.

Date	Step	What it did
2004	Continental shelf coordinates registered with the UN	Began Türkiye's formal paper record of its Eastern Mediterranean shelf limits
2009 and 2012	TPAO exploration licences	Applied the claimed shelf through state-company licensing
21 September 2011	Türkiye–TRNC Continental Shelf Delimitation Agreement	Signed two days after the Greek Cypriot administration began unilateral drilling on 19 September 2011
27 November 2019	Türkiye–Libya Maritime Jurisdiction Delimitation MoU	Delimited jurisdiction between the two coasts across the sea between them
18 March 2020	Outer limits of continental shelf registered with the UN	Placed Türkiye's outer limits formally on the UN record
16 April 2025	Marine Spatial Planning of the Republic of Türkiye unveiled	Presented a national plan covering the Black Sea, Aegean and Mediterranean
12 June 2025	Plan recorded with IOC-UNESCO	Lodged the position with a UN body for the first time, per Ankara
24 July 2025	Presidential Circular	Created an Inter-Agency Coordination Board under the Ministry of Foreign Affairs

The parallel Greek Cypriot track began earlier. The Republic of Cyprus (the Greek Cypriot administration, GCASC in Turkish official usage) concluded an EEZ agreement with Egypt in 2003, with Lebanon in 2007 and with Israel in 2010. Türkiye objects to all three. It says the 2003 Egypt agreement overlaps its continental shelf through Blocks 1, 4, 5, 6 and 7, and that the Lebanon and Israel agreements disregard the rights of the Turkish Cypriots.

What the 2025 plan is

Maritime spatial planning is a public process for analysing and organising human uses of the sea: shipping, fisheries, energy, cables, conservation and defence. IOC-UNESCO, with the European Commission, runs a well-known international programme to encourage such planning, and national plans can be notified to its information platform. Türkiye's plan, unveiled on 16 April 2025 and recorded on 12 June 2025, covers all three of its seas in one framework.

The package also included a Marine Protected Area off Finike, on the Mediterranean coast. A Presidential Circular dated 24 July 2025 then set up an Inter-Agency Coordination Board under the Ministry of Foreign Affairs to coordinate the plan's implementation across ministries. For the institutional detail, see Who Runs Türkiye's Sea Policy? The Finike Marine Protected Area and the 24 July 2025 Presidential Circular.

Sovereign rights on the ground

Türkiye pairs its paper record with operations. Its national drillships Fatih, Yavuz, Kanuni and Abdülhamid Han, and survey vessels such as Oruç Reis and Barbaros Hayreddin Paşa, completed eight major Eastern Mediterranean wells: Alanya-1, Finike-1, Karpaz-1, Güzelyurt-1, Mağusa-1, Narlıkuyu-1, Lefkoşa-1 and Selçuklu-1. The register is set out in Eight Wells, Four Drillships.

Key Players & Positions

Greece

Athens holds that its islands, including those near the Turkish coast, generate continental shelf and EEZ in the same way as mainland territory under UNCLOS, and that delimitation should follow the median line between relevant coasts. It considers the Türkiye–Libya MoU legally void because it disregards Greek islands lying between the two coasts, notably Crete. Greece signed a partial EEZ delimitation with Egypt in August 2020 and a delimitation with Italy earlier that year. As an EU member it is also bound by the EU maritime spatial planning framework (Directive 2014/89/EU), and Greek officials have contested Turkish plans and maps that they say overlap Greek maritime zones. Greek positions are best read in the Greek Foreign Ministry's own statements and its letters to the UN.

The Republic of Cyprus (Greek Cypriot administration)

The Greek Cypriot administration, which represents itself as the Republic of Cyprus, relies on its 2004 EEZ law and its bilateral agreements with Egypt, Lebanon and Israel. It argues that it is entitled to license hydrocarbon activity in its declared EEZ and that Turkish activity there violates its sovereign rights. It does not accept that the Turkish Cypriots hold a separate claim, presenting revenue sharing as something for a future settlement.

The European Union

EU Council conclusions have repeatedly expressed solidarity with Greece and the Republic of Cyprus and called Turkish drilling activities in disputed areas unlawful. The EU's own positions treat UNCLOS as reflecting customary law. Ankara answers that the EU is not a party to the dispute and has no competence to adjudicate maritime delimitation.

Egypt and Libya

Egypt, which signed the 2003 agreement with the Greek Cypriot administration and the 2020 partial delimitation with Greece, rejects the Türkiye–Libya MoU. Libya's eastern-based House of Representatives has also rejected it, while the authorities in Tripoli at the time of signing concluded it. The Libyan domestic split is part of the context in which the MoU is contested.

The TRNC and the Turkish Cypriots

The Turkish Republic of Northern Cyprus (TRNC), recognised only by Türkiye, signed the 2011 continental shelf agreement with Ankara. It has put forward hydrocarbon cooperation and revenue-sharing proposals (2011, 2012 and 2019) that remain on the table in Turkish and TRNC accounts.

IOC-UNESCO

IOC-UNESCO is a scientific and technical body. It promotes ocean science and planning and does not delimit boundaries or rule on competing claims. Critics of the 2025 step cite this as a reason not to over-read it, and any fair account must say so plainly.

🇹🇷 Official Policy · Primary Sources on File

Türkiye's Position on the Record

Türkiye's Position on the Record

• Equity, not island-driven cut-off. Ankara argues that maritime delimitation must produce an equitable result based on coastal geography and proportionality, and that islands lying close to a long mainland coast cannot cut off that coast's projection. Basis: the equity principle in ICJ and arbitral practice (North Sea 1969, Libya/Malta 1985, Romania v. Ukraine 2009) and Türkiye's statements in the Ministry of Foreign Affairs' published position on maritime jurisdiction areas.
• The 2025 plan is a recording of an existing position. According to the Turkish Foreign Ministry and Presidency, the Marine Spatial Planning of the Republic of Türkiye, unveiled on 16 April 2025 and recorded with IOC-UNESCO on 12 June 2025, puts the Black Sea, Aegean and Mediterranean positions in a UN body's records for the first time. Basis: the plan's announcement and recording, and the 24 July 2025 Presidential Circular establishing the Coordination Board under the Foreign Ministry.
• A continuous legal chain. Ankara presents 2025 as consistent with its 2004 UN coordinates, the 21 September 2011 Türkiye–TRNC agreement, the 27 November 2019 Libya MoU and the 18 March 2020 registration of outer limits with the UN. Basis: the bilateral texts and UN filings themselves.
• Turkish Cypriots are equal co-owners of the island's resources. Türkiye holds that the Turkish Cypriots have inherent and equal rights over offshore hydrocarbons, so unilateral Greek Cypriot agreements with Egypt (2003), Lebanon (2007) and Israel (2010) lack legal effect against them. Basis: the 1960 partnership structure under the Zurich and London Agreements and the 1960 Treaty of Guarantee; see The Cyprus Dossier.
• No EU competence, no Seville Map. Ankara rejects the Seville Map, which would confine Türkiye's jurisdiction to a narrow strip in the Gulf of Antalya, and argues the EU has no jurisdiction over delimitation. Dialogue remains open: President Erdoğan's 2020 call for an Eastern Mediterranean Conference including all coastal states and the Turkish Cypriots stands. See Fact Check: Is the Seville Map a Legal Maritime Boundary?.

The legal reasoning in plain language

The argument has three steps. First, the starting point is the coast: Türkiye's 870 km mainland coast is far longer than the coasts of the small islands facing it, and a proportionate result should reflect that. Second, the relevant case law shows that courts and tribunals have reduced or ignored the effect of small islands when they would distort an otherwise fair line. Third, because Türkiye is not a party to UNCLOS, the benchmark is customary law as shown in those decisions, not the convention's text alone.

Greece's reply is that UNCLOS Article 121 gives islands full entitlements and that Türkiye cannot cherry-pick treaty norms. Both views are stated here with their sources so the reader can test them: the UNCLOS text, the ICJ judgments and the two governments' own filings.

Why Ankara chose a planning route

A spatial plan is a domestic instrument. It does not need another state's consent, and it locates uses of the sea in a framework familiar to the international ocean-science community. According to Turkish officials, it also lets Türkiye show its approach to conservation, energy, shipping and fisheries together, rather than leaving the file to be read only through naval incidents. Whether that approach changes any state's legal position is a separate question; what it does is create a dated document that can be cited.

Source Comparison

The same event reads differently depending on the source. The table compares typical framings, which readers should check against the underlying documents.

Question	Typical international or Greek/Greek Cypriot framing	Turkish primary-source framing
What happened on 12 June 2025?	A technical notification of a national spatial plan with limited legal weight	The first recording of Türkiye's Black Sea, Aegean and Mediterranean positions with a UN body
Does it create rights?	No; IOC-UNESCO does not delimit boundaries	It is not a delimitation but a documented, planned and published position consistent with earlier UN filings
Role of islands	Islands generate full maritime zones under UNCLOS Article 121	Islands close to a long mainland coast cannot cut off its projection under equity
Who may rule on the boundary?	UNCLOS rules, the ICJ or arbitration, with the EU backing members	Delimitation requires agreement or a tribunal on equitable principles; the EU has no competence
Cyprus	The Republic of Cyprus holds EEZ rights	Turkish Cypriots are equal co-owners; unilateral deals lack effect against them
Relevance of the Libya MoU	Void because it ignores Crete and other islands	A valid bilateral delimitation between two coasts

Why was it so little reported?

Three explanations are consistent with the record, though they are analysis and not proven fact. First, the step was administrative and technical, and there was no naval standoff, which is what usually draws headlines. Second, international coverage of Eastern Mediterranean maritime issues tends to be built around European Union and Greek or Greek Cypriot sources, so a Turkish filing in a scientific forum sat outside the usual feed. Third, the legal significance requires reading a chain of filings across two decades, which wire reporting rarely does. This is why The Unspoken File treats it as a file to be assembled from primary documents. For other network analyses, see Monitor of Nations and The Political Anatomy.

What to watch

• Implementation: how the Inter-Agency Coordination Board under the Foreign Ministry works in practice, as set out in the 24 July 2025 Circular.
• Counter-filings: any notes verbales or letters to the UN from Greece, the Republic of Cyprus, Egypt or Libya referring to the 2025 plan.
• Greek and EU planning: how Greek national plans under the EU directive treat the zones Türkiye claims.
• The Cyprus track: the 15 October 2024 New York UN meeting and what follows, since Ankara links offshore rights to the status of the Turkish Cypriots.
• Dialogue proposals: whether the 2020 Eastern Mediterranean Conference proposal or the TRNC's revenue-sharing proposals are revived.

Key Terms & Related Guides

• Blue Homeland (Mavi Vatan): Türkiye's maritime jurisdiction doctrine covering the Black Sea, Aegean and Eastern Mediterranean, anchored in continental shelf rights and equity. The network explainer Crossroads Review: Blue Homeland and the Eastern Mediterranean covers it from another angle.
• Continental shelf and EEZ: the seabed rights of a coastal state, and the 200-nautical-mile zone for resources, respectively.
• Marine spatial planning (MSP): a public process for organising uses of the sea, promoted by IOC-UNESCO.
• Principle of equity (hakkaniyet ilkesi): the rule that delimitation must reach a fair result, taking coastal geography and proportionality into account.
• Seville Map: a maximalist map prepared for the EU by Greek and Greek Cypriot sources that Ankara rejects as legally invalid.
• GCASC and TRNC: the Greek Cypriot Administration of Southern Cyprus (the internationally recognised Republic of Cyprus) and the Turkish Republic of Northern Cyprus.
• TPAO: the Turkish Petroleum Corporation, the state energy company that holds Türkiye's exploration licences.

Related reading on this site:

• About The Unspoken File: Mission, Perspective and Editorial Team
• Editorial Principles: How The Unspoken File Sources, Separates Fact From Position and Corrects Errors
• The Cyprus Dossier: Article IV of the 1960 Treaty of Guarantee and the Legal Basis of 20 July 1974
• Fact Check: Is the Seville Map a Legal Maritime Boundary?
• Eight Wells, Four Drillships
• Reader FAQ: Sources, Method and Perspective

For the Cyprus negotiating record that sits behind the offshore dispute, see The Worldlogue on the Cyprus negotiation record, 1977 to 2024.

Perspective Note

The Unspoken File publishes this analysis from a perspective that presents and defends Türkiye's official positions and legal theses, and we state this openly to our readers. Claims are attributed to primary sources such as treaty texts, UN documents, archival records and official statements, so that readers can verify them independently. Sections marked 'Türkiye's Position on the Record' reflect official Turkish policy as stated by Turkish government sources. This article is published by The Unspoken File Editorial Team.