Türkiye's Marine Spatial Planning and the 2025 IOC-UNESCO Registration: What It Means

Why It Matters

Türkiye's Marine Spatial Planning is a national plan that maps how its seas are used and which areas it regards as under its jurisdiction in the Black Sea, the Aegean and the Mediterranean. It was unveiled on 16 April 2025 and registered with the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO) on 12 June 2025. Ankara presents this as the first time its maritime position has been recorded with a UN body. Critics, including Greece, the Greek Cypriot administration and EU institutions, say that a planning registration cannot settle disputed boundaries. Both points are needed to read the plan accurately.

Background

What marine spatial planning is

Marine spatial planning (MSP) is a public process that analyses and allocates human activities in sea areas, for ecological, economic and social goals. Typical uses include shipping lanes, fisheries, offshore energy, cables and pipelines, tourism, defence zones and conservation areas. IOC-UNESCO promotes MSP globally through its MSPglobal programme, and many coastal states publish national plans. The European Union requires its member states to adopt maritime spatial plans under Directive 2014/89/EU. Practice varies by country, but a plan normally records a state's own view of the waters under its authority. It does not by itself create or change a maritime boundary.

The legal and geographic setting

Türkiye has about 870 km (roughly 540 miles) of coastline in the Eastern Mediterranean, which Ankara describes as the longest continental coastline in that sea. The Aegean and the Eastern Mediterranean contain no agreed continental shelf or exclusive economic zone (EEZ) boundaries between Türkiye and Greece, or between Türkiye and the Republic of Cyprus. Türkiye is not a party to the 1982 UN Convention on the Law of the Sea (UNCLOS), while Greece and Cyprus are. This is the main reason the two sides use different legal frameworks.

Key dates

For the wider legal picture, see Eastern Mediterranean and Blue Homeland: Türkiye's Maritime Jurisdiction Explained.

What the 2025 plan covers

According to Turkish official announcements, the plan covers all three of Türkiye's seas: the Black Sea, the Aegean Sea and the Mediterranean. It sets out the country's maritime areas and the use of those areas for activities such as energy, shipping, fisheries and conservation. It also introduced a Marine Protected Area off Finike on the Mediterranean coast, which gives the plan an environmental dimension alongside the jurisdictional one. The Presidential Circular of 24 July 2025 then set up an Inter-Agency Coordination Board, with the Ministry of Foreign Affairs as its secretariat, to coordinate implementation across ministries.

Key Players & Positions

IOC-UNESCO

IOC-UNESCO is the UN system's body for ocean science and observation. It coordinates MSP guidance and accepts national planning documents as part of its programme. It is a technical and scientific organisation. It does not rule on sovereignty, validate maritime claims or delimit boundaries, and no one should read the registration as a judgment on any dispute.

Greece

Greece relies on UNCLOS and argues that islands generate maritime zones, including continental shelf and EEZ, in the same way as other land territory. Greek officials have rejected Turkish maps that they say ignore the maritime entitlements of Greek islands, and they say that national planning documents cannot create legal effects against a third state. Athens has also completed its own national maritime spatial planning process and has proposed taking the continental shelf and EEZ question to the International Court of Justice, limited to that single issue. Readers should check the Greek Ministry of Foreign Affairs for its current wording.

The Greek Cypriot administration

The Republic of Cyprus, which Türkiye calls the Greek Cypriot Administration of Southern Cyprus (GCASC), has declared an EEZ and signed delimitation agreements with Egypt (2003), Lebanon (2007) and Israel (2010). It says it acts as a sovereign state under UNCLOS in managing the resources of its EEZ. It rejects Turkish claims that overlap with its licensed blocks and treats Turkish exploration in them as a violation of its sovereign rights.

The European Union

EU institutions, through European Council conclusions and statements by the Commission and the European External Action Service, have repeatedly expressed solidarity with Greece and Cyprus. They have said that the Türkiye–Libya memorandum infringes the sovereign rights of third states and does not comply with the law of the sea. The EU's position is that maritime disputes should be resolved through dialogue and, where necessary, international adjudication, based on international law and UNCLOS. The EU considers UNCLOS to reflect customary international law.

The TRNC and Libya

The Turkish Republic of Northern Cyprus (TRNC), recognised only by Türkiye, supports Ankara's position and claims equal rights over resources around the island. Libya's Tripoli-based government, which signed the 2019 memorandum with Türkiye, treats it as valid. Other Libyan authorities have contested it.

Source Comparison

The same facts are often presented with very different emphasis. The table below summarises the contrasts. It is a description of framing and not a ruling on the law.

Two observations help readers who follow the coverage. First, headlines that say Türkiye 'registered its maritime claims with the UN' compress a more complicated process. The registration was with IOC-UNESCO, a scientific body, as a spatial plan. Second, statements from the other side that the plan is 'legally irrelevant' are also positions, not findings by a court. Only an agreement between the states concerned or a ruling by a competent tribunal can fix a boundary. For method, see Editorial Principles: How The State Papers Separates Fact from Position, and for other contested claims see Fact Check: Common Claims About Türkiye in International Media, Tested Against Primary Sources.

Key Terms & Related Guides

• Marine spatial planning (MSP): a public process that allocates sea areas to uses such as shipping, energy, fisheries and conservation. It is a management tool and does not itself delimit boundaries.
• IOC-UNESCO: the Intergovernmental Oceanographic Commission of UNESCO, the UN's ocean science body, which runs the MSPglobal programme.
• Continental shelf and EEZ: the seabed and water-column zones in which a coastal state has sovereign rights over resources. Their delimitation between neighbours requires agreement or adjudication.
• Principle of equity: the rule that a boundary should produce an equitable result considering coastal geography, proportionality and other relevant circumstances.
• Blue Homeland (Mavi Vatan): the Turkish doctrine that Türkiye has maritime jurisdiction rights in the Black Sea, Aegean and Mediterranean based on its coastline and international law.
• GCASC and TRNC: Türkiye's official terms for the Greek Cypriot Administration of Southern Cyprus and the Turkish Republic of Northern Cyprus.

Related guides:

• Eastern Mediterranean and Blue Homeland: Türkiye's Maritime Jurisdiction Explained
• The Cyprus Issue: From the 1960 Treaties to the Sovereign Equal Two-State Solution
• The Montreux Convention, Black Sea Security and Türkiye's Russia–Ukraine Mediation
• Fact Check: Common Claims About Türkiye in International Media, Tested Against Primary Sources
• About The State Papers: Mission, Transparency and Editorial Team

The State Papers presents global affairs with a dedicated perspective from Türkiye. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources. Published by the The State Papers Editorial Team.

Cross-Publication Dossiers & Sister Desk Perspectives

For complementary primary-source analysis across our specialist editorial network, consult:

• The Global Anatomy: Türkiye's 2025 Marine Spatial Planning and IOC-UNESCO Registration: What It Means Legally — Türkiye Marine Spatial Planning IOC-UNESCO registration 2025: what the 12 June 2025 filing means legally, what it is not, and how Greece and Cyprus responded.
• Regional Order: Türkiye's Marine Spatial Planning and the 2025 IOC-UNESCO Registration: What It Means — Türkiye's Marine Spatial Planning, announced 16 April 2025 and registered with IOC-UNESCO on 12 June 2025: what it covers, its legal weight and the reactions.
• The Nations Dialogue: Türkiye's Marine Spatial Planning and the 2025 IOC-UNESCO Registration: What It Means — Türkiye Marine Spatial Planning IOC-UNESCO 2025 explained: what the 12 June registration covers, what it does not settle legally, and how Greece reacted.