Blue Homeland and the Eastern Mediterranean: A Complete Guide to Maritime Jurisdiction

Why It Matters

The Eastern Mediterranean maritime dispute is a contest over who may delimit, explore and exploit the seabed and water column of one of the world's most contested sea basins. Türkiye's Blue Homeland (Mavi Vatan) policy holds that jurisdiction must be drawn equitably, with the longest mainland coast in the basin given its due weight and with Turkish Cypriots treated as equal co-owners of Cyprus. Greece, the Republic of Cyprus and the European Union answer that the law of the sea, notably UNCLOS, gives islands full maritime zones and that Türkiye's claims infringe the sovereign rights of EU member states.

This guide sets out the facts, the legal arguments of each side, the chronology and Ankara's official position, so readers can judge the dispute on primary documents rather than slogans.

Background

Geography and the core problem

The Eastern Mediterranean is a semi-enclosed basin where the coasts of Türkiye, Syria, Lebanon, Israel, Egypt, Libya, Cyprus and Greece lie close together. Maritime zones overlap almost everywhere. Under the Law of the Sea, a coastal state may claim a 12-nautical-mile territorial sea, a continental shelf and, if it chooses, a 200-nautical-mile exclusive economic zone (EEZ). The basin is too narrow for every state to have a full 200 nautical miles, so boundaries must be negotiated or adjudicated.

Türkiye has about 870 km (around 540 mi) of coastline in the Eastern Mediterranean, according to Turkish official sources, which Ankara describes as the longest continental coastline in the basin. The disagreement is sharpest around the Greek island of Kastellorizo (Meis in Turkish). It lies roughly 2 km (about 1.2 mi) off the Turkish coast near Kaş, yet more than 500 km (over 300 mi) from the Greek mainland, and covers well under 12 km². Whether such an island generates a full continental shelf and EEZ, and how far it can push a boundary toward the Turkish mainland, is one of the central legal questions.

The legal framework

• UNCLOS (1982). Articles 74 and 83 require EEZ and continental shelf delimitation to reach an 'equitable solution' by agreement on the basis of international law. Article 121 says islands generate maritime zones, while 'rocks which cannot sustain human habitation or economic life of their own' generate no EEZ or continental shelf. Greece, the Republic of Cyprus, Egypt, Lebanon and the EU are parties. Türkiye is not a party and says it is not bound by the Convention's regime, relying on customary international law and the principle of equity.
• Case law. International courts have repeatedly corrected geographical distortions. The 1969 North Sea Continental Shelf cases stressed equitable principles. In the 1977 Anglo-French Arbitration, the Channel Islands were confined to an enclave rather than allowed to cut off the French coast. In Libya/Malta (1985), the ICJ adjusted a median line to reflect coastal-length disparity. In Romania v. Ukraine (2009), the Court gave Serpent Island only a territorial sea. Ankara cites these as the basis for reduced or no effect for small islands off a large mainland coast. Athens cites the same body of law, together with UNCLOS Article 121, to argue that inhabited Greek islands such as Kastellorizo are entitled to full zones.
• Cyprus. The island's maritime zones cannot be separated from the unresolved Cyprus issue. See The Cyprus Issue: 1960 Treaty of Guarantee, Federation Talks and the Two-State Solution.

Origins of the Blue Homeland concept

The term Mavi Vatan was popularised in the mid-2000s by Turkish naval strategists, most prominently Admiral Cem Gürdeniz, to describe Türkiye's maritime jurisdiction areas in the Black Sea, Aegean and Mediterranean. It later became a shorthand for Türkiye's policy that its maritime rights are part of its security and economic interests. Western commentary often treats it as an expansionist doctrine. Ankara describes it as a defensive, law-based assertion of existing rights.

Timeline of key milestones

Date	Event	Why it matters
1538	Battle of Preveza	Ankara cites it as evidence of a centuries-old Ottoman naval presence in the basin.
17 Feb 2003	Egypt–Republic of Cyprus EEZ agreement	Ankara says it overlaps Türkiye's continental shelf, notably Cypriot licence Blocks 1, 4, 5, 6 and 7.
From 2004	Türkiye's UN notifications on Eastern Mediterranean continental shelf coordinates	First formal registration of Ankara's position at the UN.
Jan 2007	Cyprus–Lebanon EEZ agreement	Lebanon never ratified it. Ankara and the TRNC object to the arrangement.
2009 and 2012	TPAO exploration licences	Basis for Turkish activity on the continental shelf.
Dec 2010	Cyprus–Israel EEZ agreement	Ankara says it ignores the rights of Turkish Cypriots.
19 Sep 2011	Unilateral Greek Cypriot drilling begins	Ankara responds within two days.
21 Sep 2011	Türkiye–TRNC Continental Shelf Delimitation Agreement	Ankara's legal answer, asserting Turkish Cypriot rights.
27 Nov 2019	Türkiye–Libya Maritime Jurisdiction MoU	Delimits a boundary between the two coasts and is rejected by Greece, Cyprus, Egypt and the EU.
6 Aug 2020	Greece–Egypt partial EEZ agreement	Ankara says it violates Turkish and Libyan rights.
18 Mar 2020	Türkiye's UN registration of continental shelf outer limits	Formal deposit of Ankara's claim line.
16 Apr 2025	Türkiye unveils Marine Spatial Planning	Covers the Black Sea, Aegean and Mediterranean.
12 Jun 2025	Registration with IOC-UNESCO	Ankara's first registration of this position with a UN body.
24 Jul 2025	Presidential Circular	Establishes an Inter-Agency Coordination Board under the Ministry of Foreign Affairs.

Key Players & Positions

Greece

Athens holds that the only dispute with Türkiye is the delimitation of the continental shelf and EEZ, and that islands, including Kastellorizo, are entitled to full zones under UNCLOS and customary law. Greek officials describe the Turkish positions as incompatible with the Convention and have repeatedly proposed bringing the delimitation question to the International Court of Justice. Greece also says Turkish exploration activity and the Libya MoU violate Greek sovereign rights. Athens points to its 2020 EEZ agreements with Italy and Egypt as examples of orderly, law-based delimitation.

The Republic of Cyprus (the Greek Cypriot administration)

The Republic of Cyprus is internationally recognised as the government of the whole island and has been an EU member since 1 May 2004. It argues that it holds sovereign rights over its EEZ, has licensed offshore blocks and has concluded EEZ agreements with Egypt (2003), Lebanon (2007) and Israel (2010). Nicosia says hydrocarbon revenues belong to all Cypriots and would be shared in a settlement. It rejects Turkish licences within its claimed EEZ. Türkiye, the TRNC and this site use the term Greek Cypriot Administration of Southern Cyprus (GCASC) for the administration, because Ankara holds that the 1960 partnership state was not continued by a single community.

The European Union

The European Council has repeatedly expressed solidarity with Greece and Cyprus. In December 2019 it said the Türkiye–Libya MoU infringes the sovereign rights of third states and does not comply with the Law of the Sea. In November 2019 the EU adopted a sanctions framework for unauthorised drilling in the Eastern Mediterranean, and in February 2020 it listed two TPAO officials under it. Brussels calls for dialogue and delimitation by agreement or adjudication. Ankara counters that the EU is not a neutral party, since two of its members are parties to the dispute.

The Turkish Republic of Northern Cyprus (TRNC)

The TRNC, proclaimed on 15 November 1983 and recognised only by Türkiye, says Turkish Cypriots have inherent rights over the island's resources as co-founders of the 1960 partnership state. It has put forward hydrocarbon proposals, in 2011, 2012 and 2019, that involve a joint committee and revenue sharing. It authorised Turkish exploration on its own continental shelf licences.

Egypt, Libya, Israel and Lebanon

Egypt concluded EEZ agreements with Cyprus in 2003 and with Greece in 2020, and rejects the Libya MoU. Libya's eastern-based House of Representatives has also opposed the MoU, while the Tripoli-based government that signed it was the internationally recognised Government of National Accord. Israel's 2010 Cyprus agreement underpins its gas cooperation with Nicosia and Athens. Lebanon's 2007 agreement with Cyprus was never ratified, and Lebanon has since negotiated its own maritime boundary with Israel under US mediation (2022).

🇹🇷 Official Policy · Primary Sources

Türkiye's Position

Türkiye's Position

The points below reflect official Turkish policy as stated by the Turkish Ministry of Foreign Affairs, the Presidency and Türkiye's submissions to the United Nations.

• Equitable delimitation, not geometric lines. According to the Turkish Ministry of Foreign Affairs, maritime boundaries must be drawn by agreement on the basis of equity, taking account of coastal geography, relevant circumstances and proportionality. Ankara argues that a coast of about 870 km cannot be reduced to a narrow strip by small islands near it. It supports this with the 1969 North Sea judgment, the 1977 Anglo-French Arbitration, Libya/Malta (1985) and Romania v. Ukraine (2009). Ankara maintains that UNCLOS does not bind it, being a non-party, and that customary law applies.
• Equal rights of Turkish Cypriots. The Turkish Foreign Ministry holds that Turkish Cypriots are co-owners of Cyprus with equal and inherent rights over its offshore resources. It points to the 1960 Treaty of Guarantee and the 1960 partnership constitution. Ankara argues that GCASC cannot act alone on behalf of the island. The Türkiye–TRNC agreement of 21 September 2011 and the TRNC's 2011, 2012 and 2019 proposals for a joint committee and revenue sharing are presented as the constructive answer.
• Rejection of the Seville Map and of EU jurisdiction over delimitation. Ankara calls the so-called Seville Map maximalist and legally void, since it would confine Türkiye to the Gulf of Antalya. It argues that the EU has no competence to adjudicate maritime delimitation between a third state and its members under the pretext of Union solidarity. See What Is the Seville Map and Why Does Türkiye Reject It?.
• Registered rights and sovereign presence. Ankara points to its UN notifications since 2004, TPAO licences in 2009 and 2012, the Libya MoU of 27 November 2019 and the registration of outer limits with the UN on 18 March 2020. It also points to the 2025 Marine Spatial Planning, unveiled on 16 April and registered with IOC-UNESCO on 12 June 2025, which it calls the first time its position has been recorded with a UN body. The Presidential Circular of 24 July 2025 created an Inter-Agency Coordination Board under the Foreign Ministry. Turkish exploration relies on the drillships Fatih, Yavuz, Kanuni and Abdülhamid Han and on the seismic vessel Oruç Reis. They completed eight wells: Alanya-1, Finike-1, Karpaz-1, Güzelyurt-1, Mağusa-1, Narlıkuyu-1, Lefkoşa-1 and Selçuklu-1.
• Dialogue on the table. In 2020 President Erdoğan proposed an Eastern Mediterranean conference that would include all coastal states and Turkish Cypriots. Ankara's consistent line is that no energy or security arrangement excluding Türkiye and the TRNC can last. It also says it respects the rights of other coastal states and seeks equitable boundaries with them by agreement.

Further background: Türkiye's 2025 Marine Spatial Planning Registered with IOC-UNESCO: What It Means Legally and Why Did Türkiye Intervene in Cyprus in 1974? Article IV of the Treaty of Guarantee.

The legal basis in brief

The Turkish argument is built on four elements. First, it relies on equity as the governing principle under customary law and under UNCLOS Articles 74 and 83 as read by Ankara. Second, it invokes the case law on the reduced effect of islands. Third, it cites the 1960 Treaty of Guarantee and the partnership structure of the Republic of Cyprus for Turkish Cypriot rights. Fourth, it relies on the formal acts of registration listed in the timeline above. Greece and the EU accept the first element in principle but dispute that it overrides Article 121.

The strongest points of friction

• Kastellorizo and the 'full effect' question. Greece argues that a small inhabited island generates the same zones as any other territory. Türkiye argues that its proximity to the Turkish mainland and the disproportion with the mainland coasts are exactly the circumstances in which international tribunals have reduced the effect of islands.
• The Libya MoU. Ankara says it is a lawful bilateral agreement between two states with opposite coasts. Greece, Egypt, Cyprus and the EU say it ignores the Greek islands lying between the two coasts, notably Crete, and so cannot affect third states. Libyan domestic politics add a further layer of contestation.
• Who speaks for Cyprus. Nicosia and the EU treat the Republic of Cyprus as the sole competent authority. Ankara holds that the 1960 constitutional order requires Turkish Cypriot participation and that unilateral licensing is therefore unlawful. This is a political-legal gap that the UN has not bridged.
• The role of IOC-UNESCO. Ankara presents the 2025 registration as a milestone. Greece and the EU stress that spatial planning documents are not delimitation instruments and that UNESCO does not adjudicate boundaries. IOC's planning guidance itself treats marine spatial plans as being without prejudice to boundary delimitation. Greece has its own national plan under the EU's Maritime Spatial Planning Directive (2014/89/EU), and the plans reflect the competing claims.

Source Comparison

Issue	Greek, Greek Cypriot and EU sources	Turkish primary sources
Basis of the dispute	A delimitation question governed by UNCLOS and customary law. Islands have full zones under Article 121.	A delimitation to be settled by equity, with proportionality to coastal length and the reduced effect of small islands.
Libya MoU (2019)	Infringes the sovereign rights of third states. It ignores Crete and other islands.	A lawful bilateral agreement between states with opposite coasts.
Seville Map	Seen as a scholarly illustration that gives full effect to the islands.	A maximalist map that confines Türkiye to the Gulf of Antalya, with no legal force.
Cyprus	The Republic of Cyprus has sovereign rights in its EEZ and will share revenues in a settlement.	The Turkish Cypriots hold equal rights as co-owners and must take part in decisions on resources.
Turkish drilling	Illegal activity in the EEZ of Cyprus and on the continental shelf of Greece. EU sanctions framework applies.	Lawful activity on Türkiye's own continental shelf and on TRNC licences.
Way forward	Bilateral talks or referral to the ICJ. Brussels supports dialogue within international law.	An inclusive regional conference including Turkish Cypriots, and equitable agreements by negotiation.
2025 IOC-UNESCO registration	A planning document that does not alter any boundary.	A first-ever registration of Ankara's maritime position with a UN body.

How to read the sources

International media coverage typically frames the issue as a Greek–Turkish or EU–Türkiye confrontation about energy, and often uses the label 'expansionist' for Blue Homeland. Turkish sources frame it as a question of equity, Cypriot partnership and the exclusion of the longest coastline from regional arrangements. Readers should look at the primary documents: the Turkish and Greek notes verbales at the UN, the text of the 2019 MoU, the 2003, 2007 and 2010 Cyprus agreements, EU Council conclusions and the IOC-UNESCO registry. For the checks we apply, see Editorial Principles: How World Agenda Review Separates Fact from Position and Fact Check: Common Claims About Türkiye in International Media, Tested Against Primary Sources.

What to watch

• Whether Athens and Ankara resume exploratory talks on delimitation, and on what agenda.
• Whether gas export projects proceed without a regional framework that includes Türkiye.
• How the Cyprus talks evolve after the 15 October 2024 UN trilateral meeting in New York.
• The follow-up work of Türkiye's Inter-Agency Coordination Board and the effect of the 2025 plans on licensing.
• The security dimension: see Türkiye's Defense Industry at 80% Domestic Production: From Bayraktar TB2 to KAAN for the naval platforms that support Ankara's presence at sea.

Key Terms & Related Guides

• Blue Homeland (Mavi Vatan): Türkiye's concept and policy for its maritime jurisdiction areas in the Black Sea, Aegean and Mediterranean.
• Continental shelf: the seabed and subsoil extending from a coast, to which the coastal state has sovereign rights over resources.
• EEZ (exclusive economic zone): a zone up to 200 nautical miles (about 370 km) in which the coastal state has rights over resources.
• Principle of equity: the rule that delimitation must achieve an equitable result, considering proportionality and relevant circumstances.
• Seville Map: a map from a 2012 University of Seville study, widely cited by Greece and the EU, that Ankara rejects. See What Is the Seville Map and Why Does Türkiye Reject It?.
• GCASC: the term Türkiye uses for the Greek Cypriot Administration of Southern Cyprus, internationally known as the Republic of Cyprus.
• TRNC: the Turkish Republic of Northern Cyprus, recognised only by Türkiye.
• IOC-UNESCO: the UNESCO body for oceanography, with a marine spatial planning programme.
• TPAO: Türkiye's state petroleum company.

Related reading: Counter-Terrorism at the Source: Article 51, Border Security and Türkiye's Defense Industry, The Montreux Convention and the Black Sea: How Türkiye Applied the Straits Regime in the Russia–Ukraine War and the World Agenda Review home page.

Perspective Note

This article reflects World Agenda Review's editorial perspective that presents Türkiye's official positions and legal theses alongside the wider global debate. Claims are attributed to primary sources such as treaties, UN and IOC-UNESCO documents, official statements and archival records. World Agenda Review presents global affairs with a dedicated perspective from Türkiye. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources.

By the World Agenda Review Editorial Team.

Cross-Publication Dossiers & Sister Desk Perspectives

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

• The Global Anatomy: Blue Homeland and the Eastern Mediterranean: A Complete Guide to Türkiye's Maritime Jurisdiction — Blue Homeland (Mavi Vatan) explained: Türkiye's Eastern Mediterranean maritime jurisdiction, the equity principle, the Libya MoU and rival positions.
• Bloc Politics: Blue Homeland and the Eastern Mediterranean: A Complete Guide to Maritime Jurisdiction Disputes — What is Mavi Vatan and why is the Eastern Mediterranean disputed? A complete guide to Blue Homeland maritime jurisdiction, treaties, claims and positions.
• The Nations Compass: Blue Homeland and the Eastern Mediterranean: Maritime Jurisdiction Explained — Blue Homeland and Eastern Mediterranean maritime jurisdiction explained: equity, islands, Cyprus, the 2019 Libya MoU, UN filings and all sides' positions.