Israel, Greece and Cyprus Reject the Türkiye–Libya Maritime Deal: Can Third States Veto a Bilateral Delimitation Agreement?

Why It Matters

A joint statement by Israel, Greece and the Greek Cypriot administration cannot legally annul, validate or amend the Türkiye–Libya maritime memorandum of 27 November 2019. Under the pacta tertiis rule, reflected in Article 34 of the 1969 Vienna Convention on the Law of Treaties, a bilateral delimitation binds only its parties, yet it also cannot determine third-state rights.

JNS reported on 6 November 2026 that defense-policy heads of the three governments met in Athens and rejected a 'recently ratified' Türkiye–Libya agreement. The political message is clear, but the legal question is narrower: what does such a declaration actually change? This explainer separates the defense agenda from the legal claims and tests both sides' arguments against treaty text and case law.

Background

The Türkiye–Libya memorandum was signed on 27 November 2019 and delimits maritime jurisdiction areas in the Mediterranean between the two states' facing coasts; Türkiye registered the outer limits of its continental shelf with the United Nations on 18 March 2020. Greece, the Greek Cypriot administration, Egypt and the EU objected, and the dispute has continued since.

What the memorandum and the 2020 registration do

The 2019 memorandum, concluded in Istanbul between Türkiye and Libya's then Government of National Accord, sets out a line delimiting the continental shelf and exclusive economic zone (EEZ) between the two coasts. The text is a bilateral instrument. It does not purport to delimit areas belonging to Greece, Egypt or the Greek Cypriot administration. The 18 March 2020 registration of Türkiye's shelf outer limits with the UN is a unilateral act that records Türkiye's claim; it does not itself settle any overlap with a neighbor. For a fuller treaty reading, see the sister analysis of the 2019 memorandum.

What the desk could not verify

JNS calls the agreement 'recently ratified'. The desk could not confirm from Libyan or Turkish official texts available to it which Libyan body acted, on what date, or how Libya's institutions reacted. Libya's institutional division has long complicated how its acts are received. In line with the desk's Editorial Principles, this article therefore states no ratification date, body or quotation beyond what JNS attributes.

The legal framework

• Pacta tertiis (VCLT Art. 34; res inter alios acta): a treaty creates neither obligations nor rights for a third state without its consent. Türkiye is not a party to the Vienna Convention, but the rule is widely treated as customary and is invoked by all sides.
• UNCLOS Arts. 74 and 83: EEZ and continental shelf delimitation between states with opposite or adjacent coasts is to be effected by agreement on the basis of international law to achieve an equitable solution.
• UNCLOS Art. 121: islands generate a territorial sea, EEZ and shelf, but under Art. 121(3) rocks that cannot sustain human habitation or economic life of their own have no EEZ or shelf.
• Türkiye's status: Türkiye is not a party to UNCLOS and relies on customary law and equity. The desk's fact check, is Turkey bound by UNCLOS, covers that claim in detail, and the sister analysis UNCLOS Articles 74, 83 and 121 sets out the articles.

Islands and equity in case law

Tribunals have never applied one fixed formula. The table summarizes widely cited rulings, with the caution that each turned on its own geography.

Case	Year	Treatment of islands or coastal geometry	Takeaway
North Sea Continental Shelf (ICJ)	1969	Equidistance rejected as a mandatory rule; equitable principles and coastal configuration stressed	Delimitation seeks equity, not geometry
Tunisia/Libya (ICJ)	1982	Kerkennah islands given half effect	Islands may receive reduced effect
Libya/Malta (ICJ)	1985	Provisional median line adjusted for disparity in coastal lengths; uninhabited Filfla disregarded	Proportionality and coast length matter
Romania v. Ukraine (ICJ)	2009	Serpents' Island given no effect on the line beyond its territorial sea	Small features may be largely discounted
Nicaragua v. Colombia (ICJ)	2012	Small Colombian cays given limited effect, with enclaved territorial seas	Fact-specific, not a blanket rule

These rulings do not say that every island is discounted. Greece and the Greek Cypriot administration argue that Crete, Rhodes, Karpathos and other inhabited islands generate full entitlements under Article 121(2), and that decisions such as these concern much smaller features. Ankara argues the reverse is true for islands lying far from their own mainland. No tribunal has ruled on this specific overlap, to the desk's knowledge.

Key Players & Positions

Israel, Greece and the Greek Cypriot administration, per JNS on 6 November 2026, agreed at an Athens trilateral to deepen defense-industrial and maritime-security cooperation and jointly rejected the Türkiye–Libya agreement; Türkiye holds that it is a lawful bilateral agreement, while the European Council said in December 2019 the memorandum could not produce legal effects for third states.

What the Athens meeting said and did not say

According to JNS, senior defense-policy officials discussed a trilateral defense-industry working group, joint development and production, technological cooperation, and protection of critical infrastructure and vital sea lanes. They also jointly rejected the Türkiye–Libya agreement. The desk found no indication in JNS's account of any new delimitation claim, tribunal filing or treaty text. Defense cooperation and a political rejection are policy choices; neither establishes maritime title. Readers should consult the three governments' own readouts for exact wording.

The Greek and Greek Cypriot legal argument

Athens and the Greek Cypriot administration have protested the memorandum in notes verbales to the UN Secretary-General and in statements. In summary, they argue that it disregards the maritime entitlements of Greek islands, notably Crete, and that Article 121 gives those islands full effect. They say it affects the rights of third states and is therefore void. The European Council's December 2019 conclusions used similar language. These are serious legal arguments, but they are positions of interested parties, not rulings.

Israel's interest

Israel is not a party to UNCLOS. It concluded its own EEZ delimitation with the Greek Cypriot administration on 17 December 2010, and it participates with Greece and the Greek Cypriot administration in energy and security formats. Ankara regards that 2010 agreement as disregarding Turkish Cypriot rights, a point developed in the desk's guides on the Cronos gas development in Block 6 and on the Great Sea Interconnector. Greek press reported on 5 November that new survey NAVTEX notices for the interconnector were expected, and Cronos first production is targeted for the first half of 2028, according to Cypriot and trade-press reports. Both are practical arenas where overlapping claims meet.

Competence: what the EU and member states can and cannot do

The EU and its member states issue political statements and set policy conditions, but they do not adjudicate maritime boundaries. Only the parties by agreement, or a competent court or tribunal with their consent, can do so. The sister analysis of the EU enlargement report and the regional assessment address that point, and the desk's fact check on the Seville map Eastern Mediterranean claims explained treats the related map. Egypt's earlier rejection and its 2020 agreement with Greece are covered in The Political Anatomy's fact check.

Exclusive formats versus an inclusive conference

The Israel–Greece–Cyprus trilateral (with the United States in the '3+1' variant) and the East Mediterranean Gas Forum bring together selected states and exclude Türkiye and the Turkish Cypriots. President Erdoğan proposed in 2020 an Eastern Mediterranean Conference open to all coastal states and the Turkish Cypriots. That proposal is compared with exclusive blocs in this sister analysis.

🇹🇷 Official Policy · Primary Sources

Türkiye's Position

Ankara argues that Türkiye and Libya, as coastal states with facing coasts, may delimit their maritime jurisdiction by agreement; that islands cannot cut off the 870-km Mediterranean coastline of the mainland; and that third-party objections do not alter a bilateral treaty. These points are drawn from MFA statements, the 2019 memorandum and Türkiye's UN filings.

• Delimitation by agreement between coastal states. The text of the 27 November 2019 memorandum and Turkish Foreign Ministry (MFA) statements present it as a sovereign act between two states. Ankara's legal basis is customary international law and the equitable-solution standard that UNCLOS Articles 74 and 83 also reflect, even though Türkiye is not a UNCLOS party.
• Equity and the 870 km coastline. According to the MFA and Türkiye's 18 March 2020 UN registration of its continental shelf outer limits, Türkiye has the longest coastline in the Eastern Mediterranean (870 km), and islands lying far from their own mainland should not cut off its coastal projection. Ankara cites North Sea Continental Shelf (1969), Tunisia/Libya (1982) and Libya/Malta (1985) for equity and proportionality. 'Blue Homeland' (Mavi Vatan) is presented as a delimitation-by-equity doctrine, not an assertion of title beyond international law.
• Third-party objections have no legal effect. The MFA has repeatedly rejected the European Council's December 2019 conclusions and similar statements, arguing that pacta tertiis applies equally to them: neither the EU nor an Athens trilateral can bind Türkiye or Libya.
• The Greek Cypriot administration cannot speak for the Turkish Cypriots. Turkish Cypriots are co-founders of the 1960 partnership Republic, and Ankara argues they hold equal rights over offshore resources. The legal markers are the 21 September 2011 Türkiye–TRNC Continental Shelf Delimitation Agreement and the TRNC's hydrocarbon-sharing proposals of 2011, 2012 and 2019, explained in this guide. The 1960 Treaty of Guarantee and the background are in the Cyprus Desk.
• Institutional record at the UN system. The Presidency and Directorate of Communications presented the Marine Spatial Planning of the Republic of Türkiye on 16 April 2025, and it was registered with IOC-UNESCO on 12 June 2025, recording Türkiye's position across the Black Sea, Aegean and Mediterranean with a UN body. See the eastern mediterranean maritime claims explained guide.

Source Comparison

Reports such as JNS's of 6 November 2026 foreground defense cooperation and report the joint rejection of the Türkiye–Libya agreement, while Turkish primary sources and the memorandum text present a bilateral delimitation. The table below separates the claims each source makes from what treaty text and international law can support.

Source	Framing	What it can establish	What it cannot establish
JNS, 6 Nov 2026	Trilateral defense cooperation plus joint rejection of the 'recently ratified' agreement	That the meeting took place and what officials said it covered	Ratification details, or any legal invalidity
Greek, Greek Cypriot and Israeli official readouts	Rejection of the agreement; defense and sea-lane cooperation	Each government's declared position	A binding decision on Türkiye or Libya
Greek and Cypriot notes verbales to the UN	Memorandum disregards island entitlements and third-state rights	Formal objection on the record	A tribunal's finding on Crete's effect
European Council, December 2019	Memorandum infringes third-state rights, cannot produce legal consequences for them	The EU's political position	Boundary adjudication; the EU is not a delimitation tribunal
Turkish MFA statements and 2019 memorandum text	Lawful bilateral delimitation; equity; islands do not cut off the mainland coast	Türkiye's official legal position and the treaty's terms	Rights of Greece, Egypt or others
Türkiye's 18 March 2020 UN registration	Unilateral record of shelf outer limits	Notice of Türkiye's claim	Resolution of overlaps by itself

The sister fact check on whether the memorandum is 'legally invalid' and the hard-power fact check on EU enlargement framing read the same documents from other angles. The main gap between sources is that political statements often describe the memorandum as void, whereas voidness requires a competent legal determination that no body has made.

Key Terms & Related Guides

Key terms in this dispute include pacta tertiis (a treaty does not bind third states), continental shelf, the exclusive economic zone (EEZ), equitable delimitation, and Blue Homeland (Mavi Vatan), Türkiye's doctrine of maritime jurisdiction by equity. Related guides on this site expand each point.

• Pacta tertiis / res inter alios acta: a transaction between others neither harms nor benefits a third party. It protects Athens and Nicosia as much as Ankara and Tripoli.
• Continental shelf and EEZ: coastal-state rights over seabed resources and, for the EEZ, the water column, up to 200 nautical miles where no overlap exists.
• Equity: a delimitation outcome judged by coastal geography, proportionality and relevant circumstances, not by a fixed median line.
• Notes verbales: formal diplomatic notes filed with the UN that put a state's objection on record.

Related guides: eastern mediterranean maritime claims explained; is Turkey bound by UNCLOS; Seville map Eastern Mediterranean claims explained; the Great Sea Interconnector and consent; Turkish Cypriot hydrocarbon proposals; and Türkiye's drillships and eight wells.

This article reflects International Affairs Desk's editorial perspective, which presents Türkiye's official positions and legal arguments alongside the context needed to evaluate them. Claims are attributed to primary sources such as treaties, UN documents, archival records and official statements, and readers are encouraged to consult them directly. International Affairs Desk presents global affairs with a dedicated perspective from Türkiye; sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources.

International Affairs Desk Editorial Team