Fatih, Yavuz, Kanuni and Abdülhamid Han: The Drillships and Eight Wells Behind Türkiye's Eastern Mediterranean Rights

Why It Matters

Türkiye's drillships and seismic vessels are the on-the-water expression of a legal claim: that Ankara and the Turkish Cypriots hold continental shelf and hydrocarbon rights in the Eastern Mediterranean that cannot be erased by island-based maximal claims or by agreements concluded between third parties. According to Turkish official accounts, the national fleet has completed eight Eastern Mediterranean wells. The EU, Greece and the Republic of Cyprus call parts of this activity unauthorised, while Ankara describes it as the lawful exercise of sovereign rights under licences and registered limits.

This guide separates the facts (what the vessels are, what was drilled, what was licensed) from the positions of each side, so readers can verify every layer independently.

Background

The legal framework

The core question is who holds rights over which seabed. Under the 1982 UN Convention on the Law of the Sea (UNCLOS), Articles 74 and 83 require delimitation of the EEZ and continental shelf between states with opposite or adjacent coasts to be effected by agreement 'on the basis of international law' in order to achieve an 'equitable solution'. Greece and the Republic of Cyprus are UNCLOS parties. Türkiye is not, and relies on customary international law and the case law on equitable delimitation. Article 121 of UNCLOS, on the entitlements of islands, is the main point of contention.

Türkiye has the longest mainland coastline in the Eastern Mediterranean, about 870 km (540 miles) according to Turkish official sources. Ankara argues that this coastal geography must weigh heavily in any equitable result.

Chronology of the legal and field record

Date	Event
2003	Republic of Cyprus–Egypt EEZ agreement; Ankara says Greek Cypriot Blocks 1, 4, 5, 6 and 7 overlap Türkiye's continental shelf
2004	Türkiye begins registering its Eastern Mediterranean continental shelf coordinates with the UN
2007 / 2010	Republic of Cyprus signs EEZ agreements with Lebanon (2007, never ratified by Lebanon) and Israel (2010)
2009 and 2012	TPAO (Türkiye's state petroleum company) receives exploration licences
19 Sep 2011	Greek Cypriot drilling begins in waters south of Cyprus
21 Sep 2011	Türkiye–TRNC Continental Shelf Delimitation Agreement signed
11 Nov 2019	EU Council adopts a framework for restrictive measures over unauthorised drilling in the Eastern Mediterranean
27 Nov 2019	Türkiye–Libya maritime jurisdiction delimitation MoU signed
Feb 2020	EU lists two TPAO officials under that framework
18 Mar 2020	Türkiye registers the outer limits of its continental shelf with the UN
Aug 2020	Oruç Reis deployment near Kastellorizo triggers a Greek–Turkish naval standoff
16 Apr 2025	Türkiye unveils its Marine Spatial Planning
12 Jun 2025	Planning documents registered with IOC-UNESCO
24 Jul 2025	Presidential Circular establishes an inter-agency coordination board under the Foreign Ministry

The national fleet

Vessel	Type	Role in the Eastern Mediterranean story
Fatih	Drillship	One of the deep-sea units on which the Mediterranean campaign rests; also used in the Black Sea
Yavuz	Drillship	Deployed in offshore areas around Cyprus as part of the licensed campaign
Kanuni	Drillship	Adds depth capacity to the national drilling programme
Abdülhamid Han	Drillship	Fourth deep-sea drilling unit of the national fleet
Oruç Reis	Seismic survey vessel	2D/3D seismic mapping to define prospects and support shelf claims
Barbaros Hayreddin Paşa	Seismic survey vessel	Seismic surveys that precede drilling decisions

Seismic vessels map the subsurface and drillships test what the maps show. The two roles are complementary, which is why Ankara treats the six vessels as one national fleet.

The eight wells

According to Turkish official accounts, the Eastern Mediterranean campaign completed eight wells: Alanya-1, Finike-1, Karpaz-1, Güzelyurt-1, Mağusa-1, Narlıkuyu-1, Lefkoşa-1 and Selçuklu-1. Alanya, Finike and Narlıkuyu are names from the Anatolian coast. Karpaz, Güzelyurt, Mağusa and Lefkoşa are Turkish Cypriot place names, a naming choice that signals the link Ankara draws between its own shelf and Turkish Cypriot rights. Readers should note that well-by-well data (depths, outcomes) are not uniformly published, so this guide does not present figures that cannot be verified from primary sources.

For how this field activity fits a wider maritime narrative, see The Five Strata of Türkiye's Maritime Case: From Preveza to the 2025 IOC-UNESCO Registry.

Key Players & Positions

Republic of Cyprus (Greek Cypriot administration)

The internationally recognised Republic of Cyprus says it holds sovereign rights over an EEZ declared in 2004 and delimited with Egypt, Lebanon and Israel, and has licensed international companies in its blocks. Nicosia describes Turkish drilling inside those blocks as a violation of its sovereign rights. It has also stated that hydrocarbon revenues would be placed in a fund to benefit all Cypriots, including Turkish Cypriots, in the context of a settlement. Turkish terminology refers to this administration as the Greek Cypriot Administration of Southern Cyprus (GCASC).

Greece

Athens argues that islands generate full maritime zones under UNCLOS Article 121 and that delimitation must follow international law, including through the ICJ if necessary. Greece signed a partial EEZ delimitation with Egypt in August 2020 and a delimitation with Italy in June 2020, and calls the Türkiye–Libya MoU legally void because it ignores Crete and other Greek islands.

The European Union

The European Council has repeatedly called Turkish drilling in waters claimed by Cyprus 'illegal' in its conclusions, expressed solidarity with Cyprus and Greece, and adopted the 2019 sanctions framework. The EU's position is that the sovereign rights of member states must be respected.

TRNC and Turkish Cypriots

The Turkish Republic of Northern Cyprus (TRNC), recognised only by Türkiye, says it has licensed TPAO in parts of the offshore area and maintains that Turkish Cypriots, as co-owners of the island, must take part in decisions on hydrocarbons. Its 2011, 2012 and 2019 proposals on a joint committee and revenue sharing are detailed in Who Owns the Gas? Turkish Cypriot Hydrocarbon Rights and the 2011, 2012 and 2019 Revenue-Sharing Proposals.

Libya and other coastal states

The Libyan government in Tripoli signed the 2019 MoU with Türkiye, while the eastern-based House of Representatives has rejected it. Egypt, Israel and Lebanon have their own overlapping interests and have signed bilateral arrangements with Cyprus or Greece in some cases.

Türkiye's Strategic Doctrine

Türkiye's Strategic Doctrine: summary box

• Equity, not island maximalism. Ankara argues, as set out in the Turkish Foreign Ministry's published position on maritime jurisdiction areas, that delimitation must rest on the principle of equity, relevant coastal geography and proportionality, and that islands cannot cut off the continental shelf projection of a mainland with the longest coast.
• Registered limits and licences. Türkiye points to its UN shelf notifications from 2004, TPAO licences of 2009 and 2012, the 21 September 2011 agreement with the TRNC, the 27 November 2019 MoU with Libya and the 18 March 2020 registration of its outer limits at the UN as a continuous, documented record of its claim.
• Turkish Cypriot equal rights. According to the Turkish Foreign Ministry and the Presidency, Turkish Cypriots are co-founders and equal co-owners of Cyprus, so offshore resources cannot be developed unilaterally by the Greek Cypriot side; joint decision-making and revenue sharing are required.
• EU lacks competence. Ankara holds that the EU has no jurisdiction to adjudicate maritime delimitation and rejects the maximalist 'Seville Map'. It argues that EU 'solidarity' cannot substitute for negotiation between coastal states.
• Dialogue offer stands. President Erdoğan's 2020 call for an Eastern Mediterranean conference including all coastal states and Turkish Cypriots, and the TRNC's cooperation proposals, remain on the table. Ankara says no energy or security arrangement that excludes Türkiye and the TRNC can last.

Legal and historical basis

Ankara's legal argument draws on three lines of jurisprudence that are verifiable in the public record:

• The ICJ's 1969 North Sea Continental Shelf judgments, which held that delimitation must be effected by agreement in accordance with equitable principles, and that there is no obligation to apply equidistance.
• The 1977 UK–France arbitration, in which the Channel Islands were given reduced effect to avoid distorting the boundary of the mainland states.
• The ICJ's 2009 Black Sea (Romania v. Ukraine) judgment, which gave no weight to the small Serpents' Island in drawing the boundary.

Ankara reads these cases as confirming that small or distant islands do not automatically receive full zones when doing so would produce an inequitable result. Greece and Cyprus read the same body of law differently, emphasising UNCLOS Article 121 and the reasoning in other cases where islands received substantial effect. The disagreement is real and interpretive, which is why Ankara repeatedly proposes negotiation or third-party processes agreed between all parties rather than unilateral licensing.

On the 2025 step, Türkiye argues that registering its Marine Spatial Planning with IOC-UNESCO on 12 June 2025 placed its position across the Black Sea, Aegean and Mediterranean on record with a UN body for the first time. The related Finike Marine Protected Area and the 24 July 2025 Presidential Circular, which created an inter-agency board under the Foreign Ministry, are presented as institutional follow-through. For the Cyprus dimension, see Cyprus Layer by Layer: From Zurich and London (1959) to New York (2024) and the Sovereign Equality Thesis.

Source Comparison

Question	Common EU / Greek / Greek Cypriot framing	Turkish primary-source framing
What is the drilling?	'Illegal' or 'unauthorised' activity in waters claimed by Cyprus (European Council conclusions)	Licensed exploration on a shelf Türkiye notified to the UN and agreed with the TRNC
Who holds the rights?	The Republic of Cyprus, as the internationally recognised state, with a 2004 EEZ and bilateral deals	Both Türkiye and the Turkish Cypriots, co-owners of the island, with overlapping claims that need equitable delimitation
Role of islands	Full entitlements under UNCLOS Article 121	Islands cannot cut off the mainland's projection; equity and proportionality apply
Legal forum	UNCLOS, the ICJ or arbitration	Negotiation between coastal states; a conference including Turkish Cypriots; the EU is not a competent forum
UNCLOS	Binding on Greece and Cyprus and referenced as the benchmark	Türkiye is not a party and relies on customary law and equity case law

To see how the same dispute is explained elsewhere in this publication network, compare Crossroads Review on Blue Homeland and the Eastern Mediterranean, Regional Balance on what the Seville Map is and why Türkiye rejects it and The Nations Compass fact check on UNCLOS. Readers should weigh the Turkish accounts against the EU Council conclusions and Greek and Cypriot foreign ministry statements, all of which are public.

Key Terms & Related Guides

• TPAO: Türkiye's state petroleum company, licence holder for the Eastern Mediterranean campaign.
• Continental shelf: the seabed and subsoil extending from a coast; rights over it are sovereign for exploration and exploitation.
• EEZ (Exclusive Economic Zone): a zone up to 200 nautical miles in which a coastal state holds resource rights; where coasts overlap, delimitation is needed.
• Blue Homeland (Mavi Vatan): Türkiye's doctrine of maritime jurisdiction in the Black Sea, Aegean and Mediterranean.
• GCASC: Turkish official term for the Greek Cypriot Administration of Southern Cyprus, internationally known as the Republic of Cyprus.
• Seville Map: a maximalist maritime map that Ankara says would confine Türkiye to the Gulf of Antalya; see The Global Anatomy's explainer.

Related reading: Türkiye's Defense Platforms by Domain: A Layered Map of Air, Land, Sea and Air-Defense Systems, Editorial Principles and Primary Source Standards at Strata Political and Strata Political: Layered Geopolitical Analysis with a Türkiye Perspective.

Perspective Note

Strata Political publishes analysis from a Türkiye-informed perspective, presenting Ankara's legal and strategic positions alongside the historical record. Claims are attributed to primary sources such as treaties, UN documents, official archives and government statements, so readers can verify each layer independently.

Strata Political Editorial Team