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Case Concerning a Mysterious Maritime Delimitation Treaty

Why the Dispute Before the ICJ in Gabon/Equatorial Guinea Is Not About Delimitation


On 5 March 2021, the Press Office of the International Court of Justice (ICJ) announced that proceedings had been instituted in the Court by way of a Special Agreement between Equatorial Guinea and Gabon. The application pleads: “The Court is requested to determine whether the legal titles, treaties and international conventions invoked by the Parties have the force of law in the relations between the Gabonese Republic and the Republic of Equatorial Guinea in so far as they concern the delimitation of their common maritime and land boundaries and sovereignty over the islands of Mbanie/Mbane, Ccoctiers/Cocoteros, and Conga.” (emphasis added)

At first glance, it may excite some of us as a land sovereignty and a maritime delimitation case between the two states over three tiny specs of islands off the coast of Gabon in the Atlantic Ocean. However, not every case mentioning islands or oceans is a maritime delimitation case. In the Gabon/Equatorial Guinea case, the Court has not been asked to delimit the maritime boundary or determine the sovereignty over the islands; instead, the Court has been asked to determine the legality of the titles and treaties mentioned in the application to the extent that they relate to the maritime delimitation and sovereignty over the three islands. Or, in other words, the dispute is about the applicable law.

A Brief History and the Territorial Scope of the Dispute

Equatorial Guinea and Gabon have a long-standing maritime and territorial dispute over the ownership of three islands Mbanie/Mbane, Cocotiers/Cocoteros, and Congas. The dispute has been simmering since 1972 when there was a small military skirmish on the island of Mbanie/Mbane. It remained in obscurity until the hydrocarbon fields were discovered in the surrounding waters. In 2004, the leaders of both States jointly pledged before the United Nations Secretary-General Kofi Annan to negotiate a joint development zone in order to exploit the oil reserves. In 2004, the Secretary-Generalinitialized mediation through his special representative, but it had to be suspended in 2010 because of the souring relationship between the new Gabonese government and Equatorial Guinea. In 2011, at the invitation of the new UN Secretary-General Ban Ki-moon that the negotiations were restarted, with the aim of finding a mutually acceptable solution of the border dispute between the two parties for submission to the International Court of Justice. In 2016, these mediation efforts were successfully concluded.

The Legality of the Treaty that Never Was

In a relatively short application instituting the proceedings, Gabon has identified two treaties as applicable to the dispute – the Convention on the Delimitation of French and Spanish Possessions in West Africa, signed in Paris 27 June 1900; and the Convention on Demarcating the Land and Maritime Frontiers of Equatorial Guinea and Gabon, signed in Bata on 12 September 1974. While Equatorial Guinea also refers to the first treaty in the application, it does not mention the second treaty. The 1974 Convention was registered by Gabon in the UNTS database on 2 March 2004. In the same year, Equatorial Guinea has publicly objected to the inclusion of this Treaty in UNTS thrice, claiming that it had not concluded or signed the said Convention.

In the objection letter dated 7 April 2004, to the UN Secretary-General, the Ministry of Foreign Affairs of Equatorial Guinea writes that “the registration of the document does not add to or detract from the legality or value of the document […] the registration of the Gabonese document is inadmissible and improper since no convention exists between Equatorial Guinea and Gabon of 12 September 1974, or of any other date”.

The objection letter goes on to state that “Gabon has acted in bad faith by submitting the photocopies of the photocopies which are illegible, incomplete, and unsigned, and that no agreement was signed during the meeting of Heads of State on 12 September 1974, nor was any agreement on borders signed at any other time.” Explaining further that the two states have been conducting negotiations to reach an agreement concerning their disputes over sovereignty and border since before 1974. In these negotiations, Gabon has never mentioned the so-called agreement of 1974 and has always behaved as if no such agreement existed.

This letter of objection is instructive. It refers to the final note in the treaty text, which indicates that “the parties had not resolved their differences on all the essential elements of the agreement.” According to this note, which appears in the version submitted to UNTS, “both Heads of State agree to proceed later to a new drafting of Article 4 in order to conform to the Convention of 1900”. Art 4 of the 1974 Treaty prescribes the maritime frontier, nature of the river boundary and allocates the waters surrounding the islands in dispute. Yet, according to the final note, it shall be re-drafted and is thus subject to negotiations. According to the objections lodged, the fact that the provision that is supposed to delimit the maritime boundary has been left for later negotiation means that “the parties had not resolved their differences on all the essential elements of the agreement.” Thus, according to Equatorial Guinea, if some essential matters have been left unresolved, then there can be no binding Convention.

Thus, the dispute before the Court is about whether this document binds the parties. And, if it does, does it delimit the land and maritime boundary between Gabon and Equatorial Guinea?

When Are Treaties Legally Valid?

The central objection in the letters sent to the UN Depositary by the ministerial representative of Equatorial Guinea is that no agreement was concluded between Equatorial Guinea and Gabon and the 1974 Treaty that is registered is unsigned. Thus, it appears that this case requires an examination of the process of making a valid treaty in International Law. The 1969 Vienna Convention on the Law of Treaties (VCLT), which could very well considered to be laying down the regime of treaties, provides guidance in this regard. The means, modes, and methods of conclusion and entry into force of a treaty are dealt in Chapter II of the VCLT.

The point of departure in any international treaty-making is that the consent of all the States participating in the negotiation is needed for the adoption of the treaty text as unequivocally laid down in Art 9(1) of the VCLT. Art 10 further embellishes this by providing for the methods of authenticating the treaty, which may be done by an agreed method or by signature. The corresponding ILC Commentary to the Draft Articles provides that “authentication is the process by which this definitive text is established and it consists in some act or procedure which certifies the text as the correct and authentic text.” Since the 1974 Convention does not provide for any specific means of authentication, it is safe to presume that the authentication of the text was to be effected through the signatures.

According to Art 12 of the VCLT, a signature is considered to be an expression of consent when the treaty provides that signature shall have that effect. Now, the final Article 10 of the 1974 Convention is written to that effect stating that “the present Convention shall enter into force on the date of signature thereof. Done at Bata, on 12 September 1974”. However, no signatures appear on any of the three versions submitted to UNTS, even in the French and Spanish versions, which are stipulated to be originals and equally authentic. Thus, defeating any argument of this treaty having entered into force and being legally binding.

Signatures on treaties or any other instruments to be exchanged between the parties are the most common expression of state consent. In the Bay of Bengal Maritime Delimitation case, India had sought to rely on an exchange of letters between itself and erstwhile East Pakistan relating to the implementation of the land boundary terminus. However, these letters being unsigned, the Tribunal rejected the Indian argument and did not consider the “exchange of letter to be sufficiently authoritative” under Art 31(3)(a) of the VCLT (para 165 of the Award).

In the present set of facts, Equatorial Guinea objected to the form and format of the document. It argued that it was illegible, the versions in different languages did not match, and most importantly, that it remained unsigned.

The Effects of Registration of a Treaty

When reading on this controversy between Gabon and Equatorial Guinea, one may wonder what could be the effect of depositing a treaty with the UNTS? Does the registration of a treaty with the UNTS give it a legal force, as opposed to a treaty that may not have been registered? As legal practitioners and researchers around the world rely on UNTS for obtaining the texts of all major bilateral and multilateral treaties, there might be a prevalent assumption on the authenticity and correctness of the treaties found in it. Thus, the fact that the 1974 Convention was registered with the UNTS gives it a legal force contrary to the objections filed by Equatorial Guinea?

Broadly, Art 102 of the UN Charter obliges its member states to register all the treaties that they enter into after the date of entry into force of the Charter. The provisions of this article are further interpreted by the UN General Assembly through the ‘Regulations to give effect to Article 102 of the Charter of the United Nations. Art 1(2) of these regulations states that ‘registration shall not take place until the treaty or international agreement has come into force between two or more of the parties thereto.’ However, the Regulations do not assign the duty to the UN Secretariat to verify whether the treaty has entered into force. Neither do these regulations stipulate the procedure if an objection has been filed against a registration. It seems that an objection is simply published alongside the registered treaty.

An important caveat that each UNTS volume starts with is that ‘it is the understanding of the Secretariat that its action does not confer on the instrument the status of a treaty or an international agreement if it does not confer on the instrument the status of a treaty or an international agreement if it does not already have that status and does not confer on a party a status which it would not otherwise have.’ Applying this disclaimer to the controversy over the 1974 Convention, it can be said that if the 1974 Convention is considered to be not in force due to the lack of signatures, then its registration has no legal persuasion in the present case between Gabon and Equatorial Guinea.

Possible Questions and Considerations before the Court

As this case develops and the parties forward their arguments, it will become clearer which means and methods the Court will apply to examine the legality of the titles and treaties in so far they concern the delimitation. Also, since the parties reserve the right to bring other titles and treaties, it seems that the Court will have to go through a lot of documents trying to find the one true title to the territory. Interestingly, for now, it seems that this is not one of the cases where a colonial-era treaty is at the center of the dispute since both parties have listed the French Spanish Treaty of 1900 as applicable to the present dispute. It is the more contemporary 1974 Convention that is at the root of the dispute.

However, so far, it seems that one of the questions that the Court will have to examine is whether any agreement has been concluded between Equatorial Guinea and Gabon, which delimits the land and maritime boundaries between the parties. Some concomitant facts may arise showing the practice of either party allegedly or presumably carried out in the pursuance of the 1974 Convention, thereby precluding Equatorial Guinea from invalidating the Convention, as supported by Art 45 VCLT.

If for this or any other reason, the 1974 Convention is considered to be valid on the basis of counter-evidence that Gabon may present, then Equatorial Guinea might be considered bound by its provisions other than Art 4 (which stipulates that it is to be finalized on a later date). In that case, the matters concerning the boundary in river Muni, the land boundary terminus, the sovereignty over islands Mbanie/Mbane, Ccoctiers/Cocoteros, and Conga, and the allocation of territorial patches along the boundary will be seen as settled.


While the case will meander through arguments, counter-arguments, incidental proceedings, etc., the submission of further documents by the parties will clarify the picture. However, based on the application to the Court, what we can guess is (if the pleadings are not further modified) that, at the resolution of the dispute, parties will receive a judicial pronouncement on the titles and treaties which have the force of law between them. On the basis of these documents, they may proceed to negotiate to delimit their boundaries or may institute proceedings in some other judicial forum to delimit their boundaries. What we will certainly gain is jurisprudence of the Court on what constitutes a binding agreement between state parties and the link between the treaty registration system of the UN and the corresponding validation of the registered treaty.

Arpita Goswami Sachdeva
Arpita Goswami Sachdeva is a Research Fellow at the Max Planck Institute, Luxembourg, and a doctoral candidate at the University of Luxembourg. She obtained her Masters in International Law from the Graduate Institute, Geneva (IHEID) in 2019. Arpita has previously worked for the South China Sea Institute in Xiamen University, PR China.
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