In-Depth Analysis· Türkiye Libya maritime memorandum 2019 legality

The 2019 Türkiye–Libya Maritime Memorandum: Legal Basis and Reactions

What the 27 November 2019 Türkiye–Libya maritime memorandum says, the equity argument, UN registration and objections: a sourced look at its legality.

By Diplomacy Arena Editorial Team

Published: October 26, 2026

⏱ 10 min read (2,008 words)

Executive Summary & Key Facts

The Türkiye–Libya maritime memorandum was signed in Istanbul on 27 November 2019 and delimits the maritime jurisdiction areas between the two countries' coasts in the Mediterranean.
Türkiye argues the line follows the principle of equity and the mainland coastal geography of two states with opposite coasts; Greece, Egypt, Cyprus and the EU argue it ignores islands and infringes third-state rights.
No international court or tribunal has ruled on the memorandum, so claims of it being plainly 'legal' or 'void' are positions, not adjudicated findings.
Türkiye lodged the memorandum with the United Nations on 18 March 2020, and Greece, Egypt and Cyprus have contested it in their own communications to the UN.
Libyan domestic disputes over who could validly conclude the agreement, rooted in the 2015 Skhirat political agreement and the east–west split, remain part of the legal debate.

Why It Matters

The 27 November 2019 memorandum of understanding between Türkiye and Libya's then Government of National Accord (GNA) draws a maritime boundary across the Eastern Mediterranean between two states with opposite coasts. Whether it is legal is contested: Türkiye and successive Tripoli governments defend it under the principle of equity, while Greece, Egypt, Cyprus and the European Union say it disregards the maritime entitlements of islands such as Crete and affects third states. No court has settled the question, which is why the memorandum still shapes energy licensing, naval deployments and diplomacy in the region.

Background

What the memorandum says

The agreement is formally titled the Memorandum of Understanding between the Government of the Republic of Türkiye and the Government of National Accord-State of Libya on the Delimitation of the Maritime Jurisdiction Areas in the Mediterranean. It was signed in Istanbul by President Recep Tayyip Erdoğan and Fayez al-Sarraj, chairman of Libya's Presidential Council and prime minister of the GNA. The text is short.

Boundary line: Article 1 fixes the limits of the two countries' maritime jurisdiction areas (continental shelf and exclusive economic zone, EEZ) by geographic coordinates of turning points. The line runs through the sea between Türkiye's south-western coast and Libya's north-eastern coast, in the area south-east of Crete and south of Rhodes and Kastellorizo. Readers who need the exact coordinates should consult the text as lodged with the United Nations rather than secondary summaries, which often vary.
Scope: It delimits only the zone between the two parties' coasts. It does not purport to set boundaries with Greece, Egypt, Cyprus or any other state.
Cooperation and consultation: It contains provisions on resolving disputes by negotiation and on coordination of the parties' positions.

The memorandum is distinct from a separate security and military cooperation memorandum signed the same day. The Grand National Assembly of Türkiye (TBMM) approved that security text on 21 December 2019. Türkiye handled the maritime text as an executive instrument and published it in its Official Gazette in December 2019.

Chronology

Date	Event
1982 / 1985	ICJ judgments in Tunisia/Libya and Libya/Malta shape the law on equitable delimitation in this sea
2004 onward	Türkiye files continental shelf information with the UN for the Eastern Mediterranean
2011	Türkiye–TRNC Continental Shelf Delimitation Agreement (21 September)
2015	Libyan Political Agreement (Skhirat) creates the Presidency Council and GNA structure
2019-11-27	Türkiye–GNA maritime memorandum signed in Istanbul
2019-12	European Council conclusions criticise the memorandum; Greece expels Libya's ambassador
2020-03-18	Türkiye registers its position and the memorandum with the UN
2020-08-06	Greece and Egypt sign a partial EEZ delimitation agreement
2022-10	Türkiye and Libya's Government of National Unity sign a separate hydrocarbon cooperation memorandum

Key Players & Positions

Greece

Athens argues that Crete, Karpathos, Rhodes and Kastellorizo generate continental shelf and EEZ under the 1982 UN Convention on the Law of the Sea (UNCLOS), notably Article 121, and that Türkiye and Libya therefore have no common maritime boundary where the line was drawn. Greece's Foreign Ministry has called the memorandum legally non-existent and has made representations at the UN. Greece expelled Libya's ambassador in December 2019 after Libyan officials declined to present the text.

Egypt

Cairo rejects the memorandum as lacking legal effect, says it infringes Egyptian rights, and cites its own 2003 EEZ agreement with Cyprus and its August 2020 partial delimitation with Greece. Egypt has not, however, been a party to the Türkiye–Libya delimitation, and Turkish officials note that the Greece–Egypt deal itself overlaps areas Libya may claim.

Cyprus

The Greek Cypriot administration, which Türkiye does not recognise as representing the whole island, argues that the line violates its EEZ rights and sent communications to the UN. Türkiye responds that Turkish Cypriots hold equal rights over the island's offshore resources, a point developed in the guide to the Cyprus issue and the 1960 treaties.

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. Ankara replies that the EU has no competence to adjudicate maritime delimitation between other states and that the bloc's position reflects the interests of two of its members.

Libya's domestic actors

The legal debate inside Libya concerns authority rather than the line itself.

Critics in the eastern-based House of Representatives argued that the GNA could not conclude such a treaty without parliamentary approval and that the 2015 Skhirat agreement requires consensus within the Presidency Council. Parliament's leadership publicly rejected the text.
Supporters in Tripoli maintain the GNA was the internationally recognised government when it signed. In 2021 the Government of National Unity's foreign minister, Najla Mangoush, said Libya regarded the memorandum as valid. Tripoli has also defended Libyan rights against other states' offshore licensing south of Crete.
Shifting politics: Press reports have suggested that eastern authorities have at times shown interest in engaging with, or even ratifying, the text. Such reports should be treated cautiously until formal acts are published.

🇹🇷 Official Policy · Treaties, UN Records & Primary Sources

Türkiye's Position

Ankara's argument rests on equity, mainland coasts and sovereign capacity to contract. According to the Turkish Ministry of Foreign Affairs (MFA) and the Presidency, the main points are:

Equity is the governing rule. The MFA states that maritime delimitation must reach an equitable result and that, because Türkiye is not a party to UNCLOS, customary international law, including equidistance adjusted by relevant circumstances, applies. Ankara points to ICJ and arbitral practice, such as the 1977 Anglo-French award and Libya/Malta (1985), where small islands received reduced or no effect.
Mainland coasts of two opposite states. Türkiye holds the longest continental coastline in the Eastern Mediterranean, around 870 km (about 540 miles). The MFA argues that islands lying close to the Turkish mainland cannot cut off the projection of that coast and that Libya and Türkiye face each other across the sea.
Two sovereign parties, no third-state effect. The MFA has stated that the memorandum binds only its two parties and does not delimit areas belonging to other states. It argues that third states have no veto over a bilateral agreement between two coastal states.
Registration and transparency. Türkiye lodged the text with the UN on 18 March 2020, as part of the same process in which it registered the outer limits of its continental shelf. The MFA presents this as proof the arrangement is public and based on international law.
Dialogue remains open. President Erdoğan's 2020 proposal for an Eastern Mediterranean conference including all coastal states and the Turkish Cypriots, and the TRNC's earlier revenue-sharing proposals, are presented as the proper route. Ankara also rejects the maximalist Seville Map as the opposite of equitable delimitation, and situates the memorandum in its wider Blue Homeland doctrine.

Basis: UNCLOS rules on delimitation (Articles 74 and 83) reflect equitable-solution principles that Ankara regards as customary. Article 102 of the UN Charter governs registration of treaties with the UN Secretariat. Libya's competence is argued from the GNA's status as the internationally recognised government at signing, consistent with UN Security Council recognition of the 2015 arrangements.

Analysis: Where the Legal Arguments Meet

The dispute turns on three questions, none decided by a tribunal.

How much effect islands receive. UNCLOS Article 121 grants islands maritime zones, but case law shows that courts often give small or remote islands reduced effect when full effect would distort the result. Greece contends that Crete is large and populated and deserves full effect; Türkiye contends that the islands lie on the wrong side of the mainland coast.
Whether a boundary exists between the parties. The memorandum's validity as between Türkiye and Libya can be separate from its effect on others. Greece and the EU argue that the line crosses areas where Greek entitlements overlap; Türkiye says it cannot, because Greek claims are not opposable to a bilateral agreement.
Libyan constitutional authority. If a Libyan court or competent authority were to annul the memorandum, that would affect Libya's side regardless of the Turkish position. No such decision has been universally accepted inside Libya.

Because Türkiye is not a party to UNCLOS and Greece and Libya are, both sides cite the same convention differently. A neutral reading is that the memorandum is a validly concluded bilateral instrument whose opposability to third states remains disputed and could only be resolved by negotiation or adjudication.

Source Comparison

Source type	Typical framing	Main weakness or gap
Greek Foreign Ministry and UN notes	'Legally non-existent'; islands generate full zones; no common border	Rarely engages with reduced-effect case law for islands
European Council conclusions (12 Dec 2019)	Infringes third-state sovereign rights, contrary to UNCLOS	Collective political text; the EU is not a delimitation tribunal
Egyptian statements	Illegal and without effect; defends its own 2003 and 2020 agreements	Egypt's own agreements overlap with areas Libya may claim
Turkish MFA and Presidency	Equitable, bilateral, registered with the UN; mainland coasts prevail	Türkiye is outside UNCLOS, so its customary-law reading is contested
Libyan official statements (Tripoli and Tobruk)	Divided: Tripoli upholds validity; parts of the east question authority	Politics and legitimacy disputes mix with legal arguments
Academic commentary	Split; many accept that a bilateral deal is valid inter partes but see weak support for full disregard of islands	Often addresses only one side's strongest argument

A reader should check each claim against the memorandum's text, the UN communications and the case law cited, in line with our editorial principles. For other claims about Türkiye tested against primary documents, see the Fact Check Arena.

Memorandum of Understanding (MoU): Here, a binding bilateral instrument by which two states delimit maritime areas. Türkiye and Libya treat it as an international agreement; critics question its constitutional validity on the Libyan side.
Continental shelf and EEZ: Seabed and water-column rights extending from the coast, up to 200 nautical miles (about 370 km) where not overlapped by neighbours.
Equity (hakkaniyet): The principle that delimitation should produce a fair result in light of coastal geography and proportionality.
Opposable / third-state effect: Whether an agreement between two states can bind or affect others. Both sides invoke this in the debate.
GNA and GNU: Libya's Government of National Accord (2016–2021) and Government of National Unity (from 2021).

Diplomacy Arena presents Türkiye's official perspective and legal theses alongside the counter-arguments of other parties, and clearly labels analysis as distinct from reporting. Claims are attributed to primary sources such as treaty texts, UN documents, official statements and archival records, with links provided wherever available. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources. Published by the Diplomacy Arena Editorial Team.

Cross-Publication Dossiers & Sister Desk Perspectives

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

Region Scope: The 2019 Türkiye–Libya Maritime Memorandum Explained: Legal Basis, Objections and Impact — What the 27 November 2019 Türkiye–Libya maritime memorandum says, the equity and coastline argument, and objections from Greece, Cyprus, Egypt and the EU.
Archive of Nations: The 2019 Türkiye–Libya Maritime Memorandum: Text, Legal Basis and Objections — Türkiye Libya maritime memorandum 2019 legality explained: the text, equity and island effect, objections from Greece, Egypt and the EU, and UN registration.
Horizon of Nations: The 2019 Türkiye–Libya Maritime Memorandum: Legal Basis, Objections and Context — Türkiye Libya maritime memorandum 2019 explained: equity principle, UN registration, and objections from Greece, Egypt, Cyprus, the EU and Libya's debate.

Frequently asked questions

What does the 2019 Türkiye–Libya maritime memorandum do?

It sets a maritime boundary line between Türkiye's and Libya's continental shelf and EEZ claims in the Eastern Mediterranean, using coordinates listed in its text. It signed on 27 November 2019 in Istanbul, and it covers only the two parties' own areas, not those of third states.

Is the Türkiye–Libya maritime memorandum legal under international law?

There is no ruling by any court or tribunal. Türkiye and Tripoli argue that it is a valid bilateral delimitation based on equity, while Greece, Egypt, Cyprus and the EU argue that it ignores island entitlements under UNCLOS and infringes third-state rights. The honest answer is that legality is contested and depends on how islands are weighted.

Did Türkiye register the memorandum with the United Nations?

Yes. Türkiye lodged its position and the memorandum with the UN on 18 March 2020. Greece, Egypt and Cyprus have separately submitted communications to the UN disputing it. Registration records the text but does not itself decide its validity.

Why do Greece and the EU object to it?

Greece says Crete, Rhodes, Kastellorizo and other islands generate their own maritime zones, so Türkiye and Libya have no shared boundary where the line is drawn. The European Council stated on 12 December 2019 that the memorandum infringes third-state rights and cannot produce legal consequences for them.

What are the Libyan domestic objections?

Critics, mainly linked to the eastern House of Representatives, say the GNA lacked authority to conclude it without parliamentary approval under the 2015 Skhirat arrangements. Tripoli governments have maintained that the GNA was internationally recognised when it signed and that the memorandum remains valid.

Is the maritime memorandum the same as the Türkiye–Libya security agreement?

No. The two were signed on the same day but are separate. The TBMM approved the security and military cooperation memorandum on 21 December 2019, while the maritime memorandum concerns only the delimitation of jurisdiction areas.

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