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Whose Sea? A Greek International Law Perspective on the Greek-Turkish Disputes

Whose Sea? A Greek International Law Perspective on the Greek-Turkish Disputes
 Maria Gavouneli
Associate Professor of International Law at National & Kapodistrian University of Athens

International law around the definition of countries' Exclusive Economic Zones (EEZ), territorial waters or continental shelves is complex and unclear, which can lead to serious tensions when neighboring countries compete for the control of riches in their waters. Such an issue is precisely what frames the conflict between Turkey and the thousand-isles Greece. In this fourth part of our Eastern Mediterranean series, Maria Gavouneli, Associate Professor of International Law at National & Kapodistrian University of Athens, explains the complex history and regulations that have so far led to a stalemate in the process of defining maritime borders between Greece and Turkey.

Like all good neighbours, Greece and Turkey share a long history of peace, war and general acrimony – among which almost 50 years of contention over the maritime zones of the Aegean Sea. After a break of several years, the two NATO allies are close to restarting preparatory talks: the purpose of the exercise is to establish a direct communication channel between the parties, meeting on a regular basis, with the aim of facilitating a further round of negotiations on the issues outstanding between the interlocutors. It is therefore clear that, first, this is not a negotiation but rather talks about talks; and, second, the main agenda of these talks is to establish the agenda of a future negotiation between the parties.

Greece insists that the only item on such an agenda should be a maritime delimitation agreement for the continental shelf and a possible Exclusive Economic Zone in the Aegean and the Eastern Mediterranean. Turkey, on the other hand, presents a list with an ever increasing number of "unresolved issues", including questions on sovereignty over certain islands, the demilitarized status of other islands, the delimitation of the Greek territorial sea, the width of the national airspace of Greece and the control of the air traffic in the Aegean. In the following paragraphs, I will attempt a brief summary of the main issues that could and could not be included in such an agenda.

Agenda Items for Discussion: Delimitation of Maritime Zones

The delimitation of the continental shelf in the Aegean has been the main contentious issue between Greece and Turkey for the past 50 years. It has been (unsuccessfully) brought before the International Court of Justice, has been repeatedly discussed in the Security Council, has given rise to at least one delimitation agreement

After a break of several years, [Greece and Turkey], the two NATO allies are close to restarting preparatory talks.

All these have been carried out in the context of an ongoing effort to ensure access to energy resources in the region, and to safeguard energy security for the regional countries and the EU as a whole. This was the elephant in the room, that prompted the conduct of both the Greek and the Turkish delegations during the Third UN Conference for the Law of the Sea (1973-1982) and explained why Turkey eventually decided to stay out of a contractual arrangement common to almost all countries in the world. The question, however, contains several sub-issues that need to be addressed in turn.

Maritime zones for the islands

Article 121 of the Law of the Sea Convention distinguishes between islands, which are entitled to all maritime zones, and rocks, which are entitled to territorial sea as well (and a contiguous zone, if the coastal State so declares). It is generally acknowledged that the provision reflects customary law, thus as such it is binding for non-parties to the LOSC as well. The difference between "fully entitled islands" and rocks, however, had not been explored until fairly recently in the arbitration on the South China Sea, with mixed results

The true question, however, is not necessarily what entitlements islands have, but rather what their influence in maritime delimitation is. Turkey does not seem to challenge the premise that islands do generate maritime zones.It does, however, have very specific ideas as to their impact on an eventual delimitation line between the two countries. In terms of delimitation of the territorial sea, the established rule (both in article 15 LOSC and under customary law) is the median line, unless special circumstances necessitate an adjustment. Turkey accepts this premise, further indicating that the mere existence of islands constitutes a "special circumstance". The situation is significantly worse regarding the delimitation of the continental shelf and the EEZ, where, in the absence of any practical rule in articles 74 and 83 LOSC, the consistent case-law of a variety of international courts and tribunals came up with a 3-stage methodology: 

"[...] the first stage of the equidistance/relevant circumstances method involves the identification of a provisional equidistance line "using methods that are geometrically objective and also appropriate for the geography of the area in which the delimitation is to take place" […] The second stage calls for the consideration of relevant circumstances that may call for the adjustment of the provisional equidistance line in order to achieve an equitable result. The third stage consists of an ex post facto check of disproportionality of the result reached at the second stage." 

The Greek position refers explicitly to this methodology, with two additional points. First, under both article 77 LOSC and customary law, each State has exclusive sovereign rights ipso facto and ab initio on its continental shelf, which may extend up to 200 nm from the coast. 

Second, under both article 121 LOSC and customary law, all islands, irrespective of their size, have full entitlement to all maritime zones. The Turkish position is equally clear and long-standing: instead of the median line, Turkey insists that the delimitation of the continental shelf (and a possible EEZ) should be effected on the basis of equity or equitable principles, taking into account relevant circumstances with the aim of achieving an equitable solution. 

Turkey has consistently objected to any extension of the territorial sea in the Aegean Sea.

Such relevant circumstances include: the regional geography, including understanding the Aegean as a semi-enclosed sea, the configuration of the relevant coasts, the presence of islands, including their size and position, non-geographic circumstances, such as historic rights and the presence of third rights. As to the effect of islands, it is emphatically stated that islands cannot have a cut-off effect on the coastal projection of Turkey, as islands that lie on the "wrong side of the median line between two mainlands" cannot create maritime jurisdiction beyond their territorial waters, because "their presence distorts equitable delimitation". It is fairly clear that not only is this the most important issue pending between the two countries, but it is also the question on which their respective positions remain as far apart as possible. 

The extension of the territorial sea

The second important issue also relates to maritime zones, namely the width of the Greek territorial waters. Under article 3 LOSC and customary law, all coastal States may have territorial waters extending up to 12 nm from the baselines. Strictly speaking, each State acts unilaterally in declaring the extent of its territorial sea – indeed, this is one of the five unilateral acts provided for in the Law of the Sea Convention. Although not among the most strident supporters of the 12 nm limit during the UNCLOS III negotiations, Greece has consistently reserved its right to extend its territorial sea beyond its present width of 6 nm, including with a statement under article 310 LOSC at the time it ratified the Convention. 

On the other hand, Turkey has consistently objected to any extension of the territorial sea in the Aegean Sea.

An extension of the Greek territorial waters would also restore the uniformity of the Greek sovereign zones, as the Greek airspace remains at 10 nm, and would remove another bone of contention between the two countries.

During the UNCLOS III negotiations, Turkey proposed an addition to draft article 3 that would require States bordering enclosed and semi-enclosed seas to determine the breadth of their territorial sea by mutual agreement. It then reiterated this position during the final session of the Conference, suggesting that, overall, Turkey was a persistent objector in the development of any customary rule identical with Article 3 LOSC and, more specifically, considered any extension of the Greek territorial sea an abuse of right, as it would "deprive Turkey, one of the two coastal States of the Aegean, from its basic access to high seas from its territorial waters, the economic benefits from the Aegean, scientific research, etc". 

The persistent objection argument was effectively negated in 1982, when the Decree of the Council of Ministers no. 8/4742, issued on the basis of the Territorial Sea Act 2674 of 20 May 1982, maintained the Turkish territorial sea in the Black Sea and the Mediterranean Sea to 12 nm "in view of the characteristics of the seas surrounding Turkey and the principle of equity". In contrast, Turkey continued to strenuously object to any extension of the Greek territorial waters, culminating in the infamous "casus belli" Resolution of the Grand National Assembly on 8 July 1995, just before Greece ratified the Convention.

It is understood that discussions on the breadth of the Greek territorial sea in the Aegean have been included in previous rounds of talks. It is equally understood that this is unlikely to happen in the forthcoming meetings – at least under a separate chapter. It is to be reminded that, when during the discussion in Parliament for the ratification of the recent delimitation agreements with Italy and Egypt, the Greek Minister of Foreign Affairs announced an extension of the Greek territorial waters to 12 nm in the Ionian Sea, there had been prior communications with the Italian and the Albanian Governments, both neighbouring coastal States. In addition, an extension of the Greek territorial waters would also restore the uniformity of the Greek sovereign zones, as the Greek airspace remains at 10 nm, and would remove another bone of contention between the two countries.

Not for discussion: Sovereignty

Although the delimitation of maritime zones is acknowledged by both parties as the main dispute, Turkey expands its list of outstanding issues to include a multitude of other concerns, from the sovereignty of land features and the use of air space to the demilitarization of certain groups of islands in the Aegean. These issues pertain to the core of Greek sovereignty over land, sea and air territory and even challenge long (and bloodily) established borders between the two countries. As such, these contentions exceed the constraints of the bilateral context and become a major destabilization factor for the whole area. 

A revisionist reading of international treaties may well be part of a wider political strategy but, in strict legal terms, it does challenge the way States understand their commitments in an increasingly unstable world and undermine the foundations of the international system built on the ruins of World War II.   

Sovereignty and grey zones

Although the delimitation acrimony between the two countries goes back to at least the 1970s, the Turkish challenge on the sovereignty status of certain islands in the Aegean could be traced back to 1996 and the Imia incident

The Greek position is very clear in respect to maritime boundaries and distinguishes among three geographical areas with a different legal regime.

It has since developed into a wider attempt to create grey areas of sovereignty, thus effectively putting the international boundaries in the area on the line.

The Greek position is very clear in respect to maritime boundaries and distinguishes among three geographical areas with a different legal regime. First, the maritime region of the Evros estuary, to the extent of three miles into the sea, is delimited on the basis of the Athens Protocol of 26 November 1926. Second, south of the island of Samos, the maritime boundaries between the Dodecanese and Turkey are delimited by the Agreement of 4 January 1932 and the Protocol of 28 December 1932 between Italy and Turkey, to which Greece succeeded on the basis of Article 14(1) of the Peace Treaty of 10 February 1947. Third, in the in-between area from Evros to Samos, there is no agreed maritime border and consequently delimitation must be effected on the basis of the customary rule of median line. In contrast, the sovereignty of the islands in this area is determined by the 1923 Treaty of Lausanne, article 12 of which reads as follows:

"The decision taken on the 13th February 1914, by the Conference of London, in virtue of Articles 5 of the Treaty of London of the 17th-30th May 1913 and 15 of the Treaty of Athens of the 1st-14th November 1913, which decision was communicated to the Greek Government on the 13th February 1914, regarding the sovereignty of Greece over the islands of the Eastern Mediterranean, other than the islands of Imbros, Tenedos and Rabbit Islands, particularly the islands of Lemnos, Samothrace, Mytilene [=Lesvos], Chios, Samos and Nikaria [=Ikaria], is confirmed, subject to the provisions of the present Treaty respecting the islands placed under the sovereignty of Italy which form the subject of Article 15. Except where a provision to the contrary is contained in the present Treaty, the islands situated at less than three miles from the Asiatic coast remain under Turkish sovereignty."

The Turkish side insists that, in the absence of a bilateral delimitation agreement between Greece and Turkey, the whole area is subject to an agreed upon delimitation on the basis of equity, taking into account relevant circumstances with the aim of achieving an equitable solution. 

The possibility of any Greek government accepting to discuss issues pertaining to sovereignty over the islands, or indeed any part of the Greek territory, is simply non-existent.

In the aftermath of the Imia crisis in January 1996 and since, Turkey has repeatedly challenged the Greek title over certain islands in the region, even including islands in the south of Crete, which were given to Greece pursuant to Article 4 of the Treaty of London of the 17th-30th May 1913. 

The possibility of any Greek government accepting to discuss issues pertaining to sovereignty over the islands, or indeed any part of the Greek territory, is simply non-existent. The same applies to any attempt to convert the sovereignty issue into a preliminary and incidental question for the delimitation exercise, e.g. by objecting in the use of certain islands as base points from which the provisional equidistance line may be drawn.

This was an argument presented before the arbitral tribunal in the Chagos Marine Protected Area case, in which Mauritius attempted to raise the sovereignty issue, although the arbitral tribunal under Annex VII LOSC had jurisdiction only to adjudicate disputes arising from the Convention. The Arbitral Tribunal refused to adjudicate the question, but it did suggest that: "the Tribunal does not categorically exclude that in some instances a minor issue of territorial sovereignty could indeed be concerning the interpretation or application of the Convention". If the two parties were ever to reach a courtroom, both would need to consent to a particular procedure before a particular court or tribunal. It is highly unlikely that a possible compromis, the agreement whereby such a process may start, would not make provision for such an eventuality.


One of the most popular tools available to international law at the beginning of the 20th century was the obligation to demilitarize certain territories, especially those newly transferred to other States in the aftermath of the major resettlement of the European borders after World War I. The Aegean Sea was a privileged area for the application of the concept, with no less than three different regimes mandating the partial or full demilitarization of several clusters of islands: 

  • The 1923 Lausanne Treaty provided in Article 13 for the partial demilitarization of the Greek islands of Lesvos (Mytilene in the original text), Chios, Samos and Ikaria (Nikaria in the original text); 
  • The 1923 Lausanne Convention, relating to the regime of the Straits, created a fully demilitarized security regime for the whole area, imposing obligations on Greece for the islands Lemnos and Samothrace. It also imposes obligations on Turkey for both sides of the Dardanelles and into the Sea of Marmara, as well as the islands of Imvros (Gokceada), Tenedos (Bozcaada) and the Rabbit islands (Tavcan).
  • The 1947 Treaty of Peace with Italy provided in Article 14 paragraph 2 thereof for the total and permanent demilitarization of the Dodecanese islands, which were ceded to Greece in full sovereignty. 

The Turkish side suggests that all three regimes remain in place for Greece although the 1936 Montreux Convention superseded the 1923 Lausanne Straits Convention and created a new security regime for Turkey. Greece affirms that the 1936 Montreux Convention has indeed replaced the 1923 Lausanne Straits Convention in its entirety and thus both demilitarization obligations have ceased to exist. It further accepts that the other two obligations remain in place but have since become obsolete, at a time when a missile or a drone makes the presence of military forces in situ irrelevant.It does point out, however, that the 1947 Paris Peace Treaty is for Turkey res inter alios acta, as the latter was not a contracting party. Ultimately, however, all objections boil down to an argument of self-defense under Article 51 of the UN Charter and customary law: Greece argues that, in view of the situation in Cyprus since 1974 and the on-going tribulations in the bilateral relations, including the "casus belli" resolution, it simply cannot afford not to avail itself of all means necessary for its national defense. 

Concluding Remarks 

The parameters set for an eventual renewal of the preliminary talks between the two countries are certainly more political than legal. Nevertheless, it is affirmed by both parties that they should lead to a permanent settlement of the outstanding disputes, preferably by an international judicial instance. Greece has set out its preconditions in its 2015 Declaration recognizing the compulsory jurisdiction of the International Court of Justice with the express exception, inter alia, of any dispute relating to military activities and measures for the protection of its sovereignty and territorial integrity, as well as of any dispute concerning State boundaries or sovereignty over the territory of the Hellenic Republic. It is certainly true that a possible agreement between the parties could also include issues expressly excluded from such automated procedures, but in real life, the possibilities are really scarce. 

The complexity of the issues that need to be addressed in a negotiation between Greece and Turkey is simply staggering. The peace dividend would be equally great – and still missing. 



Copyright: Louisa GOULIAMAKI / AFP

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