1. Introduction

This paper considers the potential implications of the Chagos advisory proceedings in the International Court of Justice for other territorial situations.[1] At the heart of the advisory proceedings is the questionable lawfulness of the separation of the Chagos Archipelago from the territory of Mauritius in 1965, three years before Mauritius gained its independence from the UK. Drawing on the written and oral submissions of intervening states, the paper focuses on three territorial arrangements that also involved the excision of colonial territory by the administering power during the decolonization process:

    1. the Sovereign Base Areas (SBAs) in Cyprus, which were excised from the Colony of Cyprus as part of the constitutional settlement that resulted in the independence of the Republic of Cyprus in 1960, some four months before the adoption of General Assembly Resolution 1514 (XV) (the Colonial Declaration);
    2. Mayotte, one of the four islands in the Comoros Archipelago. France excised Mayotte from the rest of the Comoros on the eve of Comorian independence in 1975, ostensibly on the basis that the population of Mayotte had voted to retain links with France, even though overall the population of the Comoros (which had been administered by France as a single colony) had voted for independence;
    3. the unpopulated Scattered Islands (Iles Eparses), four of which – the Glorieuses, Juan de Nova, Europa and Bassas da India – were excised from Madagascar by France, shortly before Madagascan independence in 1960, also without consent or UN approval.


2. The Cyprus Sovereign Base Areas

The Republic of Cyprus noted in its written submission to the ICJ that its observations ‘should not be understood as defining the position of the Republic in relation to any specific situation’.[2] It was nevertheless open about its motivation for intervening in the case:

‘… at the end of British colonial rule in 1960, the United Kingdom retained two areas of the territory of the island as bases, to be used solely for military purposes. The guidance of the Court on, and the clarification of, the international legal framework governing the decolonization process and its consequences are therefore of direct interest to the Republic of Cyprus.’[3]

The retention of the SBAs by the United Kingdom was provided for in Article 1 of the 1960 Treaty of Establishment of the Republic of Cyprus:

‘The territory of the Republic of Cyprus shall comprise the Island of Cyprus, together with the islands lying off its coast, with the exception of the two areas defined in Annex A to this Treaty, which areas shall remain under the sovereignty of the United Kingdom. These areas are in this Treaty and its Annexes referred to as the Akrotiri Sovereign Base Area and the Dhekelia Sovereign Base Area.’[4]

The Republic of Cyprus argued in its written submission in the Chagos proceedings that:

‘The principle of self-determination had emerged as a rule of customary international law by 1960 at the latest; … The principle of self-determination contains a prohibition on excision of colonial territory prior to or at the time of independence.’[5]

The Cypriot submission referred to decolonization as ‘a process, not a single act; and until the process is entirely completed it generates continuing obligations for both the administering State and the international community of States as a whole, intertwined as it is with the principle of self-determination’.[6]
‘The essence of the principle of self-determination’, according to Cyprus, ‘is that it persists until such time as it has been fully realised; and an administering State can be called upon to implement, or continue or complete the implementation of, the principle as it then stands, at any time’.[7]
The submission continues, pointedly:

‘ln the current advisory proceedings, that means that the absence of continuing consent to the excision and/or the administration of a parcel of territory from an area granted independence in the 1960s triggers the obligation today to give effect to the principle of self-determination in relation to that excised parcel of territory, including by entering into negotiations aimed at resolving its future status.’[8]

Cyprus took issue with the UK’s assertion that ‘the Republic of Cyprus (among other States) “did not interpret paragraph 6 [of General Assembly Resolution 1514 (XV)] as prohibiting the adjustment of boundaries in the period preceding independence”’.[9]
Rather, Cyprus asserted that the position it took in the debate preceding the adoption of the Colonial Declaration in 1960 was that ‘matters regarding the territorial integrity of a colony or other non-self-governing territory are subject to a general prohibition on the excision of territory therefrom, and that any such excision of territory prior to or at the time of independence is inherently suspicious and in any case is not permissible without the free and continuing consent of those entitled to exercise the right of self­-determination’.[10]
In its oral submissions, Cyprus further developed the argument that even consensual excisions of colonial territory by the administering power at the point of decolonization are revocable, if and when the dismembered former colony withdraws its consent to the territorial arrangement: ‘in the … exercise of the inalienable right of self-determination a people may, by their free choice and continuing consent, agree to arrangements which allow, revocably, other States to use a part of their territory.’[11] Thus, ‘the continuing consent of the people to the maintenance of the status quo is an inherent, and at all times essential, element of self-determination’.[12]
In support of its position, Cyprus pointed to the UK government’s defence of the right to self-determination in the British Overseas Territories, drawing attention to the UK’s emphasis on ‘the continuing “overwhelming wish to remain British” of peoples of United Kingdom overseas territories’.[13]
It is significant, in Cyprus’s submission, that many official statements of the UK government ‘put stress on the free and continuing wish of the peoples of overseas territories, expressed through elections and referenda held from time to time, to remain British and to retain their status, if they so wish’.[14]
In short, the Republic of Cyprus argued that consent by a colonial people to an excision of its territory must not only be freely given: it must be ‘continuing’ even after an entity has achieved its independence, and it is ‘revocable’.
While much of the discussion in the Chagos proceedings focuses on what constitutes ‘free’ consent to an excision of colonial territory during the decolonization process, it will be interesting to see whether the ICJ endorses a requirement for continuing consent, and if so what the parameters of such a requirement will be said to be.
The endorsement by the ICJ of such a requirement could create space for Cyprus to argue that the retention of British sovereignty over the SBAs pursuant to the 1960 constitutional settlement is subject to continuing Cypriot consent.

3. Mayotte

The excision by France of Mayotte from the rest of the Comoros Archipelago took place in 1975.[15] All the states which made submissions on the merits in the Chagos proceedings accepted that an international legal right to self-determination had crystallized by that time.
Even the UK, while maintaining that self-determination had not crystallized as a right in the 1960s, referred to the Friendly Relations Declaration – General Assembly Resolution 2625 (XXV), of 24 October 1970 – as ‘the first consensus resolution on a “right” to self-determination (as opposed to a “principle”)’.[16]
The UK was more ambiguous on the relevance of territorial integrity in the exercise of the right to self-determination, arguing that territory is important in defining ‘the people’, but ‘… it does not require that the boundaries of the territory remain entirely unchanged during some unspecified period prior to independence’.[17]
Even if one accepts this caveat, the French position in relation to Mayotte is difficult to sustain as a matter of international law.
France’s justification for the excision of the island of Mayotte from the rest of the Comoros Archipelago was that in a 1974 referendum of the whole territory of the Comoros, a breakdown of the vote showed that a majority of the population of Mayotte had voted to retain links with France. The decision to view the vote on an island-by-island basis involved a policy U-turn on the part of France, whose President had asserted in October 1974, two months before the referendum, that France would give effect to the wishes of the population of the Comoros Archipelago as a whole, and that: ‘Nous n’avons pas, à l’occasion de l’indépendence d’un territoire, à proposer de briser l’unité de ce qui a toujours été l’unique archipel des Comores.’[18]
‘Exasperated’ by the French change of policy after the referendum, the local Comorian legislature, without the participation of representatives from Mayotte, unilaterally declared the independence of the Comoros Islands ‘within their colonial frontiers’ on 6 July 1975.[19] The ‘necessity of respecting the unity and territorial integrity of the Comoro Archipelago’ was reaffirmed by the General Assembly in Resolution 3385 (XXX), pursuant to which the Comoros was admitted to membership of the UN in 1975, and some nineteen further resolutions of the General Assembly followed in a similar vein, up to 1994.[20]
Neither the Comoros nor France made submissions on the merits in the Chagos proceedings.[21] However, the African Union – making submissions on behalf of its members, inter alios Comoros – referred in its submission to the requirement of ‘seeking the free consent of the population as a whole.[22]
The African Union’s submission reflects the consensus that popular opinion in a sub-unit of a colony cannot serve as a basis for the fragmentation of that colony during the decolonization process, other than in cases of consensual divorce (see for example the UN-approved decolonization of British Cameroons, Ruanda-Urundi, Gilbert and Ellice Islands, and the Trust Territory of the Pacific Islands).[23]
It seems likely therefore that any decision by the ICJ on the merits will offer no support to the French position on Mayotte (which in 2011 was accorded the status of Département d’Outre Mer), and may well further undermine it.

4. The Scattered Islands (Iles Eparses)

France excised four of the five Scattered Islands – the Glorieuses, Juan de Nova, Europa and Bassas da India – from Madagascar on 1 April 1960, shortly before Madagascar gained its independence on 26 June 1960. The islands had been administered as part of the French colony of Madagascar from 1897 onwards, but France contends that this was done merely as a matter of administrative convenience, and that it never considered the islands to be dependencies of Madagascar.[24] France also argues that Madagascar acquiesced, on separate occasions prior to and after its independence, to the detachment of the islands.[25]
These arguments did not persuade the UN General Assembly, which adopted essentially the same line as it did in relation to Mayotte (although it waited until 1979 to do so, following the assertion by France of an Exclusive Economic Zone around the islands). The General Assembly reaffirmed ‘the necessity of scrupulously respecting the national unity and territorial integrity of a colonial territory at the time of its accession to independence’, and called for ‘the reintegration of the … islands, which were arbitrarily separated from Madagascar’.[26]
Since 1990, the General Assembly has deferred consideration of the Scattered Islands, ‘probably as a result of the wishes of both countries to play down the dispute’, according to one commentator.[27]
Madagascar’s two-page written submission in the Chagos proceedings did not mention the Scattered Islands explicitly.[28] As expected, the submission endorsed the African Union’s approach on the Chagos question, citing with approval a 2017 resolution of the Assembly of the Union that states, ‘the Chagos Archipelago, including Diego Garcia, forms an integral part of the territory of the Republic of Mauritius and that the decolonization of the Republic of Mauritius will not be complete until it is able to exercise its full sovereignty over the Chagos Archipelago’.[29]
Aside from this, Madagascar argued that continued British administration over the Chagos Archipelago is ‘not likely to facilitate’ negotiations on maritime delimitation in the Indian Ocean region.[30]
While there is nothing specific in Madagascar’s submission that indicates an intention to use the Chagos proceedings as a vehicle for advancing its position on the question of the Scattered Islands, a strong finding by the ICJ that emphasizes the territorial integrity of Mauritius and the unlawfulness of the excision of the Chagos Archipelago would benefit Madagascar. Such a finding could be used by Madagascar as leverage in negotiations over maritime delimitation, for example.

5. Conclusion

None of the three cases referred to above are perfectly analogous with the excision of the Chagos Archipelago from Mauritius. For example, none entailed the forcible and covert removal of people from their homes in furtherance of the administering power’s territorial ambitions. However, all three territorial arrangements referred to in this paper could be affected by the outcome of the Chagos advisory proceedings, especially if the ICJ considers it necessary to flesh out the content and scope of the law on self-determination and territorial integrity.
Other states embroiled in territorial disputes in which issues of self-determination and territorial integrity are at stake may also be hoping that dicta emerge from the Chagos Opinion or the Separate Opinions (if any) that advance, or at least do not undermine, their causes. For instance, while references to the Falkland Islands (Malvinas) and Belize are studiously avoided in the respective submissions of Argentina and Guatemala, the seriousness with which Argentina and Guatemala (and indeed Belize) have approached the Chagos proceedings – all three states making substantial interventions – suggests that they consider their interests to be (at least potentially) engaged.[31]

* Fellow, Wolfson College, Cambridge and Lauterpacht Centre for International Law; Barrister (Lincoln’s Inn).
[1] Legal Consequences of the Separation of the Chagos Archipelago from Mauritius in 1965 (Request for Advisory Opinion) see <www.icj-cij.org/en/case/169> for the submissions of intervening states and other relevant documents in the case, including the text of the request for an advisory opinion transmitted to the ICJ pursuant to GA Res 71/292 (UN Doc A/71/L.73) 22 June 2017.
[2] Second written submission of the Republic of Cyprus, 15 May 2018 <www.icj-cij.org/files/case-related/169/169-20180511-WRI-01-00-EN.pdf> para 26.
[3] First written statement of the Republic of Cyprus, 21 February 2018 <www.icj-cij.org/files/case-related/169/169-20180212-WRI-01-00-EN.pdf> para 4.
[4] 382 UNTS (1960) 5476.
[5] Second written submission of the Republic of Cyprus (n 2) para 1.
[6] ibid para 8.
[7] ibid para 15 (emphasis added).
[8] ibid para 16 (emphasis added).
[9] ibid para 23.
[10] ibid para 24 (emphasis added).
[11] Oral submissions of the Republic of Cyprus, Verbatim Record of the Hearing of 4 September 2018 <www.icj-cij.org/files/case-related/169/169-20180904-ORA-02-00-BI.pdf> 47, 48, para 9 (emphasis in the original).
[12] ibid para 16 (emphasis in the original).
[13] ibid para 17, citing a statement of the British Secretary of State for Defence in the House of Commons: House of Commons Debates (HC Deb) (24 March 2015) vol 594, col 1302-1303 (emphasis added by Counsel for the Republic of Cyprus).
[14] Oral Submission of the Republic of Cyprus (n 11) para 17 (emphasis in the original).
[15] Art 2, Law of 3 July 1975, JO 4 July 1975, 6764.
[16] <www.icj-cij.org/files/case-related/169/169-20180514-WRI-01-00-EN.pdf> para 4.5.
[17] ibid para 4.6.
[18] President Giscard d’Estaing, press conference of 24 October 1974, cited in (1975) 21 Annuaire Français de Droit International 1067.
[19] ibid 1068.
[20] All the relevant resolutions are listed in GA Res 49/18 (28 November 1994).
[21] France made a first-round submission on 28 February 2018, arguing that the ICJ lacked jurisdiction to hear the case as it involved a bilateral dispute and the two states in question had not consented to the Court’s jurisdiction: <www.icj-cij.org/files/case-related/169/169-20180227-WRI-03-00-EN.pdf> para 19.
[22] Written submission of the African Union <www.icj-cij.org/files/case-related/169/169-20180515-WRI-01-00-EN.pdf> para 208 (emphasis added).
[23] See Chapter 3.1, The (General) Prohibition on the Fragmentation of Non-Self-Governing Territories, in J Trinidad Self-Determination in Disputed Colonial Territories (CUP 2018) 73 et seq.
[24] A Oraison, ‘A propos du différend franco-malgache sur les îles éparses du canal de Mozambique’ (1981) 85 Revue Générale de Droit International Public 461-513, 489.
[25] ibid 488-91.
[26] GA Res 34/91 (12 December 1979).
[27] A Tahindro, ‘The Implementation of UNCLOS in the Indian Ocean Region: The Case of Madagascar’ (2004) 12 African YB Intl L 349-435, 372.
[28] Written submission of Madagascar, 28 February 2018 <www.icj-cij.org/files/case-related/169/169-20180228-WRI-05-00-EN.pdf>.
[29] Para 3 of resolution Assembly/AU/Res.1 (XXVIII), adopted by the Assembly of the Union at the close of its 28th Ordinary Session held in Addis Ababa on 30 and 31 January 2017.
[30] Written submission of Madagascar (n 28) 1.
[31] See (n 1) above for links to the relevant submissions, all of which were broadly supportive of the Mauritian position. The governments of Guatemala and Belize are currently contemplating a resolution of the Guatemalan claim to Belize before the ICJ, subject to the outcome of a referendum in Belize that is due to take place on 10 April 2019 (the Guatemalan electorate has already approved the submission of the claim to the ICJ, in a 15 April 2018 referendum).