|I.||Substantive International Law - First Part|
|8.||VIOLATIONS OF INTERNATIONAL LAW AND RESPONSIBILITY OF STATES|
(Hungary / Slovakia)
Judgment of 25 September 1997
I.C.J. Reports 1997, p. 7
[pp. 55-57] 83. In order to be justifiable, a countermeasure must meet certain conditions (see Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America) Merits, Judgment, I.C.J. Reports 1986, p. 127, para. 249. See also Arbitral Award of 9 December 1978 in the case concerning the Air Service Agreement of 27 March 1946 between the United States of America and France, United Nations, Reports of International Arbitral Awards (RIAA), Vol. XVIH, pp. 443 et seq.; also Articles 47 to 50 of the Draft Articles on State Responsibility adopted by the International ·Law Commission on f:rst reading, "Report of the International Law Commission on the work of its forty-eighth session, 6 May-26 July 1996", Official Records of the General Assembly, Fifyflrst Session, Supplement No. 10 (A/51/10), pp. 144-145.)
In the first place it must be taken in response to a previous international wrongful act of another State and must be directed against that State. Although not primarily presented as a countermeasure, it is clear that Variant C was a response to Hungary's suspension and abandonment of works and that it was directed against that State; and it is equally clear, in the Court's view, that Hungary's actions were internationally wrongful.
84. Secondly, the injured State must have called upon the State committing the wrongful act to discontinue its wrongful conduct or to make reparation for it. It is clear from the facts of the case, as recalled above by the Court (see paragraphs 61 et seq.), that Czechoslovakia requested Hungary to resume the performance of its treaty obligations on many occasions.
85. In the view of the Court, an important consideration is that the effects of a countermeasure must be commensurate with the injury suffered, taking account of the rights in question.
In 1929, the Permanent Court of International Justice, with regard to navigation on the River Oder, stated as follows:
"[the] community of interest in a navigable river becomes the basis of a common legal right, the essential features of which are the perfect equality of all riparian States in the user of the whole course of the river and the exclusion of any preferential privilege of any one riparian State in relation to the others" (Territorial Jurisdiction of the International Commission of the River Oder, Judgment No. 16, 1929, P.C.I.J., Series A, No. 23, p. 27).
Modern development of international law has strengthened this principle for non-navigational uses of international watercourses as well, as evidenced by the adoption of the Convention of 21 May 1997 on the Law of the Non-Navigational Uses of International Watercourses by the United Nations General Assembly.
The Court considers that Czechoslovakia, by unilaterally assuming control of a shared resource, and thereby depriving Hungary of its right to an equitable and reasonable share of the natural resources of the Danube - with the continuing effects of the diversion of these waters on the ecology of the riparian area of the Szigetköz - failed to respect the proportionality which is required by international law.
86. Moreover, as the Court has already pointed out (see paragraph 78), the fact that Hungary had agreed in the context of the original Project to the diversion of the Danube (and, in the Joint Contractual Plan, to a provisional measure of withdrawal of water from the Danube) cannot be understood as having authorized Czechoslovakia to proceed with a unilateral diversion of this magnitude without Hungary's consent.
87. The Court thus considers that the diversion of the Danube carried out by Czechoslovakia was not a lawful countermeasure because it was not proportionate. It is therefore not required to pass upon one other condition for the lawfulness of a countermeasure, namely that its purpose must be to induce the wrongdoing State to comply with its obligations under international law, and that the measure must therefore be reversible.