Germany calls on Turkey to respect international law when conducting seismic surveys in the eastern Mediterranean

Published: 28 September 2021 Author: Stefan Talmon

Turkey and Greece have a long-standing dispute over their continental shelf and exclusive economic zone (EEZ) entitlements in the eastern Mediterranean. On 21 July 2020, tensions between the two countries flared – once again – when Turkey announced that, as part of its ongoing hydrocarbon exploration activities in the eastern Mediterranean, its seismic survey vessel “Oruç Reis” would launch a new seismic survey in areas of the Turkish continental shelf. Greece immediately objected, claiming that the survey area was within its own continental shelf because of Kastellorizo – a small Greek island of some 10 km2, located only 2 km off the Anatolian coast, some 127 km from the nearest Greek island of Rhodes and around 580 km from the Greek mainland. The Greek navy was placed on alert and the “Oruç Reis” was escorted on her mission by Turkish warships.

During a visit to Athens on 21 July 2020, Federal Foreign Minister Heiko Maas commented on the Turkish survey activities, saying:

“Regarding Turkey’s drilling in the eastern Mediterranean, we have a very clear position. International law must be respected and, for that reason, progress in EU-Turkey relations is only possible if Ankara refrains from provocations in the eastern Mediterranean.”

The Federal Foreign Office reiterated this position the following day at the regular government press conference. A spokesperson referred to the Turkish drilling activities as “provocations”.

Germany mediated between the two countries and on 28 July 2020 Turkey announced the suspension of its hydrocarbon exploration activities and its readiness to restart exploratory talks with Greece intended to lay the groundwork for formal negotiations over maritime boundaries and related issues.

On 6 August 2020, however, Greece undermined Germany’s confidence-building efforts between the two parties by signing an agreement with Egypt on the delimitation of their EEZ in parts of the eastern Mediterranean. As a consequence, on 10 August 2020 Turkey once again dispatched the “Oruç Reis” under the escort of warships to an area south of Kastellorizo. In Berlin, a spokesperson for the Federal Foreign Office declared:

“We have noted with concern this decision by Turkey to undertake further seismic surveys in the eastern Mediterranean. Foreign Minister Maas had repeatedly stated that international law must be respected and that we urgently need steps of de-escalation in the eastern Mediterranean. In this regard, further seismic surveys at this point is definitely the wrong message.”

The cabinet spokesperson added:

“It is important and urgently needed that the parties involved – Greece and Turkey – enter into direct talks with each other; that is, that they discuss the law of the sea questions at issue and, hopefully, clarify them.”

Germany continued with its mediation efforts between the two countries. Before leaving for Athens and Ankara on 25 August 2020, Foreign Minister Maas declared:

“The contentious issues surrounding the natural gas reserves in the eastern Mediterranean can only be resolved in line with international law and through a sincere dialogue.”

Germany stated that “international law must be respected” but did not specify the relevant international law. This raises the question of what international law has to say on Turkey’s seismic survey activities in the eastern Mediterranean and, in particular, whether these activities were compatible with international law.

Turkey’s drilling activities related to hydrocarbon exploration took place south of the island of Kastellorizo in an area which both Greece and Turkey claim as part of their continental shelf. The dispute between the two States resulted from the geographic location of the Greek island right in front of the Turkish mainland coast and Greece’s maximalist claim that all inhabited islands automatically generate entitlements to a full continental shelf and EEZ irrespective of their location or geographical circumstances. In the case of Kastellorizo, this would lead to an islet of some 10 km2 in size generating a continental shelf area of 40,000 km2, depriving much of the Turkish coast of a continental shelf of its own. Turkey countered Greece’s strategy of maximum claims by adopting its own maximalist strategy which denies islands in closed and semi-enclosed seas all maritime zones with the exception of a territorial sea. Neither of the two positions seems in line with international law. However, according to the principle of sovereign equality of States, pending agreement on the delimitation of overlapping maritime claims the legal positions of disputing States are equally valid. Under customary international law, reflected in Article 83 of the United Nations Convention on the Law of the Sea (UNCLOS), the delimitation of overlapping continental shelf claims shall be effected by agreement between the disputing States. Pending such an agreement, the disputing States shall make every effort to enter into provisional arrangements of a practical nature and, during the transitional period, shall refrain from taking any action that would jeopardise or hamper the reaching of the final delimitation agreement. These principles of maritime delimitations are thus also binding on Turkey, which is not a party to UNCLOS.

In a letter to the UN Secretary-General, dated 2 July 2020, Turkey last signalled its readiness to reach an agreement on the equitable delimitation of maritime jurisdiction areas with relevant coastal States. The question is thus whether Turkey’s unilateral hydrocarbon exploration activities in the disputed continental shelf area violated its obligation not to jeopardise or hamper the reaching of a final delimitation agreement with Greece. This must not be confused with the question of whether hydrocarbon exploration activities in a disputed continental shelf area by one State constitute a threat of irreparable prejudice to the sovereign rights and jurisdiction claimed by the other State – a question international courts and tribunals are usually called upon to decide in interim measures applications.

With regard to the latter, the International Court of Justice (ICJ) held in the Aegean Sea Continental Shelf case that the seismic exploration undertaken by Turkey in the areas of the Aegean Sea which were also claimed by Greece did not constitute “a threat of irreparable prejudice to the rights claimed by Greece” and, consequently, it did not order Turkey to stop its exploration activities. The ICJ based its finding, however, on a specific set of facts: the seismic exploration undertaken by Turkey, of which Greece complained, was carried out by a vessel traversing the surface of the high seas and causing small explosions to occur at intervals under water; no physical damage was done to the seabed or subsoil or to their natural resources; it did not involve the establishment of installations on or above the seabed of the continental shelf; and the exploration did not involve the actual appropriation or other use of the natural resources of the areas of the continental shelf which were in dispute.

Similarly, in its Provisional Measures Order of 25 April 2015 in the case concerning Delimitation of the Maritime Boundary Between Ghana and Côte d’Ivoire, a Special Chamber of the International Tribunal for the Law of the Sea (ITLOS)  was called upon to decide whether the unilateral exploration activities of Ghana in disputed areas of the continental shelf created “a risk of irreparable prejudice” to the rights claimed by Côte d’Ivoire. The ITLOS Special Chamber saw such a risk where exploration activities resulted in significant and permanent modification of the physical character of the seabed and subsoil of disputed continental shelf area. In addition, the Special Chamber considered that the acquisition and use of information about the resources of the disputed area gained through exploration activities could create a risk of irreversible prejudice to rights in issue. It consequently ordered Ghana to take all necessary steps to ensure that no new drilling took place in the disputed area.

In its judgment on the merits, on the other hand, the ITLOS Special Chamber held that Ghana’s extensive exploration activities in the disputed area did not violate its obligation under Article 83(3) UNCLOS not to jeopardize or hamper the reaching of a final delimitation agreement. The Special Chamber also noted that maritime activities undertaken by a claimant in a disputed area of the continental shelf prior to a final boundary delimitation could not be considered to be in violation of the sovereign rights of the other claimant if the area concerned was the subject of claims made in good faith by both claimants. This was so, even if the activities took place in areas that would ultimately be allocated to the other claimant. The two decisions in the case concerning Delimitation of the Maritime Boundary Between Ghana and Côte d’Ivoire nicely illustrate that different considerations apply to the questions of irreparable prejudice and jeopardising or hampering a final delimitation agreement.

International courts and tribunals, however, have not always kept the two questions clearly apart. In the Arbitration regarding the delimitation of the maritime boundary between Guyana and Suriname, the tribunal took the view with regard to hydrocarbon exploration activities that only unilateral acts which caused physical change to the marine environment would have the effect of jeopardizing or hampering the reaching of a final delimitation agreement. The tribunal thus distinguished between harmless seismic testing and exploratory drilling that may cause permanent damage to the marine environment. While the former was to be permissible in disputed areas the latter was considered a violation of the obligation under Article 83(3) UNCLOS. The tribunal expressly based its decision on the ICJ’s interim measures order in the Aegean Sea Continental Shelf case, overlooking that the latter was concerned with the question of irreparable prejudice and not with jeopardizing or hampering the reaching of a final delimitation agreement.

The question of whether a hydrocarbon exploration activity has the effect of jeopardizing or hampering the reaching of a final delimitation agreement must be answered, not on the basis of the physical effects of the activity, but on the basis of its likely effect on the process of reaching a final agreement. Exploration activities, both seismic testing and exploratory drilling, do not stand in the way of reaching a delimitation agreement. As the ICJ pointed out in the Aegean Sea Continental Shelf case, “exploration activity unilaterally undertaken by either of the interested States with respect to the disputed areas can[not] be creative of new rights or deprive the other State of any rights to which in law it may be entitled”. It should also be recalled that the obligation in Article 83(3) UNCLOS was not intended to preclude all activities in a disputed continental shelf area. In particular, the provision is not to stifle the ability of States to pursue economic development in a disputed area.

Germany’s call on Turkey to respect international law was thus without legal basis. The Turkish exploration activities in the eastern Mediterranean clearly represented political provocations but not a violation of international law. A final agreement on the delimitation of the continental shelf in the eastern Mediterranean ultimately does not depend on whether or not Turkey carries out exploratory drilling in disputed areas, but on the political will of the two States.

Category: Law of the sea

DOI: 10.17176/20220627-172716-0

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  • Stefan Talmon

    Stefan Talmon is Professor of Public Law, Public International Law and European Union Law, and Director at the Institute of Public International Law at the University of Bonn. He is also a Supernumerary Fellow of St. Anne’s College, Oxford, and practices as a Barrister from Twenty Essex, London. He is the editor of GPIL.

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