78 Report of the International Law Commission on the work of its fifty-third session absolute and material impossibility, and because a circumstance rendering performance more difficult or burdensome does not constitute a case of force majeure.356 (8) In addition to its application in inter-State cases as a matter of public international law, force majeure has substantial currency in the field of international commercial arbitration, and may qualify as a general principle of law.357 (9) A State may not invoke force majeure if it has caused or induced the situation in question. In Libyan Arab Foreign Investment Company and The Republic of Burundi, the arbitral tribunal rejected a plea of force majeure because “the alleged impossibility [was] not the result of an irresistible force or an unforeseen external event beyond the control of Burundi. In fact, the impossibility is the result of a unilateral decision of that State ...”358 Under the equivalent ground for termination of a treaty in article 61 of the 1969 Vienna Convention, material impossibility cannot be invoked “if the impossibility is the result of a breach by that party either of an obligation under the treaty or of any other international obligation owed to any other party to the treaty”. By analogy with this provision, paragraph 2 (a) excludes the plea in circumstances where force majeure is due, either alone or in combination with other factors, to the conduct of the State invoking it. For paragraph 2 (a) to apply it is not enough that the State invoking force majeure has contributed to the situation of material impossibility; the situation of force majeure must be “due” to the conduct of the State invoking it. This allows for force majeure to be invoked in situations in which a State may have unwittingly contributed to the occurrence of material impossibility by something which, in hindsight, might have been done differently but which was done in good faith and did not itself make the event any less unforeseen. Paragraph 2 (a) requires that the State’s role in the occurrence of force majeure must be substantial. (10) Paragraph 2 (b) deals with situations in which the State has already accepted the risk of the occurrence of force majeure, whether it has done so in terms of the obligation itself or by its conduct or by virtue of some unilateral act. This reflects the principle that force majeure should not excuse performance if the State has undertaken to prevent the particular situation arising or has otherwise assumed that risk.359 Once a State accepts the responsibil356 “Rainbow Warrior” (see footnote 46 above), p. 253. On force majeure in the case law of the Iran-United States Claims Tribunal, see G. H. Aldrich, The Jurisprudence of the Iran-United States Claims Tribunal (Oxford, Clarendon Press, 1996), pp. 306–320. Force majeure has also been recognized as a general principle of law by the European Court of Justice: see, e.g., case 145/85, Denkavit v. Belgium, Eur. Court H.R., Reports 1987–2, p. 565; case 101/84, Commission of the European Communities v. Italian Republic, ibid., Reports 1985– 6, p. 2629. See also article 79 of the United Nations Convention on Contracts for the International Sale of Goods; P. Schlechtriem, ed., Commentary on the UN Convention on the International Sale of Goods, 2nd ed. (trans. G. Thomas) (Oxford, Clarendon Press, 1998), pp. 600–626; and article 7.1.7 of the UNIDROIT Principles, Principles of International Commercial Contracts (Rome, Unidroit, 1994), pp. 169– 171. 358 ILR, vol. 96 (1994), p. 318, para. 55. 359 As the study prepared by the Secretariat (footnote 345 above), para. 31, points out, States may renounce the right to rely on force majeure by agreement. The most common way of doing so would be by 357 ity for a particular risk it cannot then claim force majeure to avoid responsibility. But the assumption of risk must be unequivocal and directed towards those to whom the obligation is owed. Article 24. Distress 1. The wrongfulness of an act of a State not in conformity with an international obligation of that State is precluded if the author of the act in question has no other reasonable way, in a situation of distress, of saving the author’s life or the lives of other persons entrusted to the author’s care. 2. Paragraph 1 does not apply if: (a) the situation of distress is due, either alone or in combination with other factors, to the conduct of the State invoking it; or (b) the act in question is likely to create a comparable or greater peril. Commentary (1) Article 24 deals with the specific case where an individual whose acts are attributable to the State is in a situation of peril, either personally or in relation to persons under his or her care. The article precludes the wrongfulness of conduct adopted by the State agent in circumstances where the agent had no other reasonable way of saving life. Unlike situations of force majeure dealt with in article 23, a person acting under distress is not acting involuntarily, even though the choice is effectively nullified by the situation of peril.360 Nor is it a case of choosing between compliance with international law and other legitimate interests of the State, such as characterize situations of necessity under article 25. The interest concerned is the immediate one of saving people’s lives, irrespective of their nationality. (2) In practice, cases of distress have mostly involved aircraft or ships entering State territory under stress of weather or following mechanical or navigational failure.361 An example is the entry of United States military aircraft into Yugoslavia’s airspace in 1946. On two occasions, United States military aircraft entered Yugoslav airspace without authorization and were attacked by Yugoslav air defences. The United States Government protested the Yugoslav action on the basis that the aircraft had entered Yugoslav airspace solely in order to escape extreme danger. The Yugoslav Government responded by denouncing the systematic violation of its airspace, which it claimed could only be intentional in view of its frequency. A later note from the Yugoslav chargé d’affaires informed the United States Department of State that Marshal Tito had an agreement or obligation assuming in advance the risk of the particular force majeure event. 360 For this reason, writers who have considered this situation have often defined it as one of “relative impossibility” of complying with the international obligation. See, e.g., O. J. Lissitzyn, “The treatment of aerial intruders in recent practice and international law”, AJIL, vol. 47, No. 4 (October 1953), p. 588. 361 See the study prepared by the Secretariat (footnote 345 above), paras. 141–142 and 252.