249
UNCLOS
119
as well as, in general, customary international law.
120
As noted by the
Tribunal, the Parties recognized that the provisions of UNCLOS Article 123 on
cooperation were “undoubtedly part of the legal background to the maritime aspects
of the present case”.
121
Since Article 123 does not distinguish between different
maritime areas, the obligation to cooperate it sets out must be regarded as applying
to internal waters as well, at least in the specific case where the internal waters of
two States border each other, as is the case with multinational bays. The Tribunal,
however, made reference to Article 123 only in a later section of the Award, devoted
to the regime of the Junction Area, rather than in the section on the regime of the
Bay. In establishing the cooperation obligations imposed on the Parties in the
Junction Area, the Tribunal mentioned “the express obligations under UNCLOS
Articles 123 [Cooperation of States bordering enclosed or semi-enclosed seas], 300
[Good faith and abuse of rights], and 301 [Peaceful uses of the seas]”,
122
thus confirming the binding nature of the obligation to cooperate.
4 Delimitation of the Territorial Sea
Most of the criticism voiced by commentators contemporary with the Final Award
concerned the delimitation of the territorial sea, with regard to both (i) the method
that the Tribunal identified as applicable to that delimitation, and (ii) its application
in practice.
As to the first aspect, the Parties agreed on the applicability of Articles 12(1) TSC
and 15 UNCLOS to the delimitation of the territorial sea. Their positions diverged,
however, with respect to the existence of historic titles or special circumstances,
123
119 Scholars debate the nature of this obligation. Some authors note that Art. 123 “is couched in the
language of exhortation…” and that “[t]his language is not consistent with any mandatory obligation to join with the States bordering such seas in the activities specified in the article” (see
Nordquist et al. (1995), p. 366), or similarly deny that it has the character of a pactum de contrahendo (see e.g. Ronzitti (1995), p. 720). Others maintain that, despite its wording, Art. 123 impose
a legal obligation to cooperate upon the riparians of an enclosed or semi-enclosed sea (Sersic
(2002), p. 330, defines it as a sui generis obligation or an obligation of good faith). Still others
qualify Art. 123 as a “strenghtened” obligation (see Cataldi (2016), p. 180).
120 See Virzo (2005), pp. 409–410. According to this view, which seems preferable, such an obligation concerns not only cooperation in the protection of the marine environment, but also in the
conservation and management of biological resources, on which see Del Vecchio (2002), pp. 224–
232. Art. 123 UNCLOS arguably reinforces these obligations.
121 Croatia/Slovenia, para. 1105. To be precise, that was Slovenia’s position. Croatia, while agreeing that the Adriatic Sea qualified “as a semi-enclosed sea for the purposes of the general applicability of UNCLOS Article 123”, specified that “this is of limited guidance to the Tribunal because
“[u]nlike the Arbitration Agreement, Article 123 proceeds on the basis that maritime territory and
sovereign rights are pertinent to territory, are to be delimited in accordance with international law,
and not in accordance with general equity” (ibidem, para. 1114).
122 Ibidem, para. 1134.
123 Slovenia claimed the existence of traditional fishing rights over the territorial sea that, both
The Law of Maritime Delimitation in the Croatia/Slovenia Final Award
UNCLOS
119
as well as, in general, customary international law.
120
As noted by the
Tribunal, the Parties recognized that the provisions of UNCLOS Article 123 on
cooperation were “undoubtedly part of the legal background to the maritime aspects
of the present case”.
121
Since Article 123 does not distinguish between different
maritime areas, the obligation to cooperate it sets out must be regarded as applying
to internal waters as well, at least in the specific case where the internal waters of
two States border each other, as is the case with multinational bays. The Tribunal,
however, made reference to Article 123 only in a later section of the Award, devoted
to the regime of the Junction Area, rather than in the section on the regime of the
Bay. In establishing the cooperation obligations imposed on the Parties in the
Junction Area, the Tribunal mentioned “the express obligations under UNCLOS
Articles 123 [Cooperation of States bordering enclosed or semi-enclosed seas], 300
[Good faith and abuse of rights], and 301 [Peaceful uses of the seas]”,
122
thus confirming the binding nature of the obligation to cooperate.
4 Delimitation of the Territorial Sea
Most of the criticism voiced by commentators contemporary with the Final Award
concerned the delimitation of the territorial sea, with regard to both (i) the method
that the Tribunal identified as applicable to that delimitation, and (ii) its application
in practice.
As to the first aspect, the Parties agreed on the applicability of Articles 12(1) TSC
and 15 UNCLOS to the delimitation of the territorial sea. Their positions diverged,
however, with respect to the existence of historic titles or special circumstances,
123
119 Scholars debate the nature of this obligation. Some authors note that Art. 123 “is couched in the
language of exhortation…” and that “[t]his language is not consistent with any mandatory obligation to join with the States bordering such seas in the activities specified in the article” (see
Nordquist et al. (1995), p. 366), or similarly deny that it has the character of a pactum de contrahendo (see e.g. Ronzitti (1995), p. 720). Others maintain that, despite its wording, Art. 123 impose
a legal obligation to cooperate upon the riparians of an enclosed or semi-enclosed sea (Sersic
(2002), p. 330, defines it as a sui generis obligation or an obligation of good faith). Still others
qualify Art. 123 as a “strenghtened” obligation (see Cataldi (2016), p. 180).
120 See Virzo (2005), pp. 409–410. According to this view, which seems preferable, such an obligation concerns not only cooperation in the protection of the marine environment, but also in the
conservation and management of biological resources, on which see Del Vecchio (2002), pp. 224–
232. Art. 123 UNCLOS arguably reinforces these obligations.
121 Croatia/Slovenia, para. 1105. To be precise, that was Slovenia’s position. Croatia, while agreeing that the Adriatic Sea qualified “as a semi-enclosed sea for the purposes of the general applicability of UNCLOS Article 123”, specified that “this is of limited guidance to the Tribunal because
“[u]nlike the Arbitration Agreement, Article 123 proceeds on the basis that maritime territory and
sovereign rights are pertinent to territory, are to be delimited in accordance with international law,
and not in accordance with general equity” (ibidem, para. 1114).
122 Ibidem, para. 1134.
123 Slovenia claimed the existence of traditional fishing rights over the territorial sea that, both
The Law of Maritime Delimitation in the Croatia/Slovenia Final Award