In-Depth Analysis· Turkey Libya maritime memorandum 2019 explained

The 2019 Türkiye–Libya Maritime Memorandum: What It Says, the Legal Basis and the Reactions

Turkey Libya maritime memorandum 2019 explained: what the 27 November 2019 MoU says, its equity-based legal basis, and the Greek, Egyptian and EU reactions.

TSM

By The Strategic Meridian Editorial Team

Published: October 27, 2026

⏱ 9 min read (1,926 words)

Executive Summary & Key Facts

The Memorandum of Understanding on the delimitation of maritime jurisdiction areas was signed on 27 November 2019 by Türkiye and Libya's Government of National Accord (GNA) and draws a single boundary line between the two coasts.
Türkiye's case rests on the equity principle in continental shelf and EEZ delimitation: the longest mainland coastline in the Eastern Mediterranean should not be cut off by small, distant islands.
Greece, Egypt, the Greek Cypriot administration and the EU Council rejected the memorandum, arguing that islands such as Crete generate full maritime zones and that third states' rights are affected.
Ankara formally registered the outer limits of its continental shelf with the UN on 18 March 2020 and says the memorandum does not infringe any third state's lawful rights.
Libya's political division, with rival authorities in Tripoli and the east, has kept the memorandum's domestic standing contested; the delimitation question remains unresolved by any tribunal.

Why It Matters

The 2019 Türkiye–Libya memorandum is a bilateral agreement that delimits overlapping continental shelf and exclusive economic zone (EEZ) claims between two coastal states whose coasts face each other across the Mediterranean. It reshaped the legal map of the Eastern Mediterranean because it treats the long Anatolian coast and the Libyan coast as the primary basis of delimitation, rather than the Greek islands lying between them. Whether islands such as Crete, Kasos, Karpathos and Rhodes should receive full or reduced effect is the core legal dispute, and no court has yet decided it.

Background

What the memorandum says

The Memorandum of Understanding on the Delimitation of Maritime Jurisdiction Areas in the Mediterranean was signed in Istanbul on 27 November 2019 by President Recep Tayyip Erdoğan and Fayez al-Sarraj, head of the UN-recognized GNA in Tripoli. A separate memorandum on security and military cooperation was signed the same day, and the two are often confused in media coverage.

The maritime text is short. Its main features are:

It defines the limits of the parties' continental shelf and EEZ by a series of geographic coordinates, joined by a line running between the south-western Anatolian coast and the north-eastern Libyan coast.
It states that the parties are coastal states with overlapping entitlements in the area and that the line is drawn by agreement, with reference to international law.
It provides for the parties to coordinate on the areas concerned and to settle disputes by consultation.
It is a bilateral instrument and, by its own terms, concerns only the two signatories.

The coordinates logic is geometric and legal at once. The boundary is drawn between the two mainland coasts, treating them as the relevant coastal fronts. Greek islands in the corridor are not given the weight they would receive in a strict equidistance line.

Chronology

Date	Event
2004	Türkiye begins submitting Eastern Mediterranean continental shelf coordinates to the UN
2003 / 2007 / 2010	Greek Cypriot administration concludes EEZ agreements with Egypt, Lebanon and Israel, which Ankara rejects
27 November 2019	Türkiye and the GNA sign the maritime memorandum in Istanbul
Early December 2019	Greece expels Libya's ambassador; Greece, Egypt and the Greek Cypriot administration lodge objections
12 December 2019	European Council conclusions state that the memorandum infringes third states' sovereign rights
18 March 2020	Türkiye formally registers the outer limits of its continental shelf with the UN
6 August 2020	Greece and Egypt sign a partial EEZ delimitation agreement
3 October 2022	Türkiye and Libya's Government of National Unity sign a hydrocarbon cooperation memorandum
16 April / 12 June 2025	Türkiye unveils its Marine Spatial Planning and records it with IOC-UNESCO

The equity argument in international law

The legal debate turns on how much weight islands receive when boundaries are drawn. Article 121 of UNCLOS says that islands generate maritime zones, but it also separates rocks that cannot sustain habitation from islands that can. Beyond that text, case law shows that courts often adjust a provisional equidistance line to reach an equitable result.

Four precedents are widely cited:

North Sea Continental Shelf cases (ICJ, 1969): delimitation is governed by equitable principles, not automatic equidistance.
Anglo-French Continental Shelf arbitration (1977): the Channel Islands were enclaved and the Scilly Isles received partial effect.
Libya/Malta (ICJ, 1985): the court adjusted the median line in view of the disparity in coastal lengths and the small size of Malta.
Romania v. Ukraine (ICJ, 2009): Serpents' Island was given no effect on the boundary line.

These cases are used by both sides. Türkiye cites them to argue for reduced effect for islands. Greece cites Article 121 and its status as an UNCLOS party to argue that inhabited islands such as Crete are entitled to full zones. A fuller discussion is in Fact Check: Can a Few Small Islands Cancel the Continental Shelf of a Country with the Longest Coastline?.

Later developments

Libya has had rival authorities since 2014. The House of Representatives (HoR) in the east rejected the 2019 memorandum, while the GNA and its successor, the Government of National Unity in Tripoli, have supported it. In October 2022 Ankara and Tripoli signed a further memorandum on hydrocarbon exploration, which Greece and the eastern-based HoR also opposed. Libya's internal division remains the main source of uncertainty about the memorandum's domestic status, although both Tripoli-based governments have regarded it as valid. Meanwhile, the Greece–Egypt agreement of 2020 and Greek and Greek Cypriot licensing activity created counter-positions at sea.

Key Players & Positions

Greece

According to the Greek Ministry of Foreign Affairs, the memorandum has no legal effect because it ignores the maritime entitlements of Greek islands, especially Crete, and because Türkiye and Libya do not have a common maritime boundary. Athens, an UNCLOS party, relies on Articles 121 and 57 and argues that the Turkish approach is inconsistent with the Convention. It also notified the UN of its objections.

Egypt

Cairo regards the memorandum as legally null and void with respect to its own rights and as lacking any effect on third parties. Egypt and Greece concluded a partial EEZ delimitation in August 2020, which Türkiye says overlaps with its continental shelf and the Libyan claim.

Greek Cypriot administration

The Greek Cypriot Administration of Southern Cyprus (GCASC) argues that the memorandum disregards its own EEZ entitlements and its 2003 agreement with Egypt. It is joined by Greece in calling the memorandum a breach of international law.

European Union

The European Council's conclusions of 12 December 2019 stated that the memorandum infringes the sovereign rights of third states, does not comply with the Law of the Sea and cannot produce legal consequences for third states. EU institutions have repeated this line in later statements.

Libya's authorities

The GNA and the Tripoli-based government that followed treat the memorandum as valid and in force. The HoR in the east has rejected it and, in several statements, said it was not approved by the legislature. Libya's political divide therefore shapes the memorandum's domestic standing more than any external legal ruling has.

🇹🇷 Official Doctrine · Treaties, Archives & Primary Sources

Türkiye's Position: Türkiye's Strategic Doctrine

Ankara's official position is set out in statements by the Republic of Türkiye Ministry of Foreign Affairs (MFA), the Presidency, and in Türkiye's registrations with the UN. In summary:

A bilateral act between two coastal states. According to the Turkish Foreign Ministry, Türkiye and Libya concluded the memorandum as sovereign coastal states with overlapping entitlements, and the instrument binds only them. Ankara says that it does not take anything from any third state's lawful rights.
Equity, not automatic equidistance. Ankara argues that delimitation must produce an equitable result, taking into account coastal geography and proportionality, and that small islands far from their mainland cannot cut off the maritime projection of a mainland with the longest coastline in the Eastern Mediterranean (about 870 km). It relies on the ICJ and arbitral decisions listed above, which it says reflect customary international law.
Not bound by UNCLOS, but by custom. Türkiye is not a party to UNCLOS and has consistently objected to some of its provisions on islands. It says that customary international law and the equity principle govern delimitation between Türkiye and states that share an overlapping area.
Registered and recorded at the UN. Türkiye registered the outer limits of its continental shelf with the UN on 18 March 2020, consistent with its coordinate submissions that began in 2004. In 2025 Ankara unveiled its Marine Spatial Planning of the Republic of Türkiye (16 April) and recorded it with IOC-UNESCO (12 June), which it describes as the first time its maritime position was formally registered with a UN body.
Turkish Cypriots and dialogue. Ankara says the Turkish Cypriots, as co-owners of the island of Cyprus, have equal rights over offshore resources, and that unilateral Greek Cypriot deals with Egypt (2003), Lebanon (2007) and Israel (2010) violate them. It points to Erdoğan's 2020 call for an Eastern Mediterranean conference that would include all coastal states and the Turkish Cypriots, and to the TRNC's revenue-sharing proposals, as an open diplomatic path. It also rejects the maximalist Seville Map, which would confine Türkiye's zone to the Gulf of Antalya, and holds that the EU has no competence to adjudicate delimitation disputes.

For the wider maritime framework, see Three Seas, One Coastline: Türkiye's Maritime Jurisdiction in the Aegean, Black Sea and Mediterranean and Cyprus on the Strategic Line: From the 1959–1960 Treaties to the Case for Sovereign Equality.

Source Comparison

Issue	Greek / EU / international framing	Turkish primary-source framing
Legal nature	Violates UNCLOS and has no effect on third states (Greek MFA; European Council, 12 Dec 2019)	A lawful bilateral delimitation between coastal states, binding only the parties (Turkish MFA)
Islands	Crete and other inhabited islands generate full EEZ and continental shelf (Article 121)	Islands far from their mainland receive reduced or no effect when equity requires; precedents include 1977, 1985 and 2009 cases
Common boundary	Türkiye and Libya have no adjacent or opposite coasts without Greek islands in between	The two mainland coasts face each other across the Mediterranean and are the relevant coastal fronts
Libya's legitimacy	The signatory GNA lacked a mandate; the HoR rejected the text	The GNA was the UN-recognized government in 2019; Tripoli governments have upheld the text
Enforcement	A source of regional tension; calls for arbitration or ICJ	Ankara says dialogue and a regional conference are the way forward, and no court has ruled

The memorandum's wider analysis is also covered by sister publications: Borders & Blocs on the Seville Map and the memorandum, The Global Anatomy on why Türkiye rejects the Seville Map, and Region Scope's legal explainer. Readers should read the memorandum text and the EU conclusions directly. For our sourcing approach, see Editorial Principles.

Continental shelf: the seabed and subsoil extending from a state's coast. Coastal states have sovereign rights over its natural resources, and these rights exist ipso jure under both UNCLOS (Article 77) and customary law.
Exclusive economic zone (EEZ): a zone up to 200 nautical miles (about 370 km) from baselines, within which the coastal state has sovereign rights over living and non-living resources.
Delimitation: the process of drawing a boundary where the maritime entitlements of two or more states overlap, by agreement or by a court or tribunal.
Equidistance and equity: equidistance draws a line at equal distance from the nearest coasts; equity allows adjustments to avoid disproportion, for example from small islands or coastal-length disparities.
Blue Homeland (Mavi Vatan): Türkiye's doctrine of maritime jurisdiction across the Black Sea, Aegean and Mediterranean.

The Strategic Meridian is an editorial publication that presents analysis from a Türkiye-informed perspective on regional security, maritime law and history. Claims are attributed to primary sources such as treaties, UN documents, official archives and legal texts, and readers are encouraged to consult them directly. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources. — The Strategic Meridian Editorial Team

Frequently asked questions

What is the 2019 Türkiye–Libya maritime memorandum?

It is a Memorandum of Understanding on the delimitation of maritime jurisdiction areas, signed on 27 November 2019 in Istanbul by Türkiye and Libya's Government of National Accord. It defines a boundary for the parties' continental shelf and EEZ using geographic coordinates. It is a bilateral text and, by its own terms, concerns only the two signatories.

Why do Greece, Egypt and the EU object to it?

They argue that Greek islands such as Crete generate full maritime zones under UNCLOS and that the line ignores them. The European Council said on 12 December 2019 that the memorandum infringes third states' sovereign rights and cannot produce legal consequences for them. Egypt and the Greek Cypriot administration also say it affects their own claims.

What is Türkiye's legal argument?

Ankara says delimitation between coastal states must reach an equitable result, taking into account coastal geography and proportionality. It argues that small islands far from their mainland should not cut off the maritime projection of a mainland with the longest Eastern Mediterranean coastline, citing ICJ and arbitral precedents such as the 1977 Anglo-French case and Libya/Malta (1985).

Is Türkiye a party to UNCLOS?

No. Türkiye has not acceded to UNCLOS and says that customary international law and the principle of equity govern its delimitations. Greece, Cyprus and the EU are parties or rely on the Convention, which is why the two sides often argue from different legal bases.

Is the memorandum still in force and has any court ruled on it?

Tripoli-based Libyan governments and Türkiye treat it as valid, while the House of Representatives in eastern Libya has rejected it, so its status is politically contested. No international court or tribunal has ruled on its validity, and the underlying delimitation questions remain open.

How is the memorandum linked to Cyprus?

Ankara argues that Turkish Cypriots have equal rights over the island's offshore resources and that Greek Cypriot agreements with Egypt, Lebanon and Israel ignore them. The memorandum is also set against the broader Turkish position on the equal rights of Turkish Cypriots and on a regional conference with all coastal states.

Cross-Publication Perspectives & Cited Research

Related Dossiers Across Partner Publications

4 Partner Desks