Abstract The ability of foreign investors to sue host states without reliance on diplomatic protection is one of the most important developments in international investment law in the post-World War II era. The rise of investor-state dispute settlement under international regimes like the Convention Establishing the International Centre for the Settlement of Investment Disputes (ICSID Convention) raises some concerns from states regarding loss of sovereignty. However, there are defences available to states when they intervene in their economies for purposes like public utility or the need to safeguard an essential interest. Thus in spite of treaty commitments that bind states to protect the investments of foreign investors within their domains, there are available defences for their intervention in their economies even if such interventions become inimical to the interests of foreign investors and could, prima facie, raise the possibility of infringements of the rights of foreign investors. One of such defences available to states is the principle of necessity. This article explores the principle of necessity in international law and how it operates as a defence for states in investor-state dispute settlement. It also conducts analysis of the Annulment Decision in the CMS v Argentina case to shed light on the principle of necessity.

中文翻译：

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国际法的必要性辩护与投资者与国家争端解决

摘要外国投资者在不依赖外交保护的情况下起诉东道国的能力是二战后国际投资法最重要的发展之一。在诸如建立国际投资争端解决中心的公约（ICSID公约）这样的国际制度下，投资者与国家之间争端解决的兴起引起了各国对主权丧失的一些担忧。但是，当国家出于公共事业或维护基本利益的目的而干预经济时，国家可以采取防御措施。因此，尽管条约承诺约束国家保护外国投资者在其领域内的投资，即使他们的干预对外国投资者的利益无益，并且从表面上看，可能会增加侵犯外国投资者权利的可能性，但仍有干预他们的经济手段的辩护。对国家可用的这种辩护之一是必要性原则。本文探讨了国际法中的必要性原则，以及它如何在投资者与国家之间的争端解决中为国家辩护。它还对CMS v Argentina案中的《废止决定》进行了分析，以阐明必要性原则。本文探讨了国际法中的必要性原则，以及它如何在投资者与国家之间的争端解决中为国家辩护。它还对CMS v Argentina案中的《废止决定》进行了分析，以阐明必要性原则。本文探讨了国际法中的必要性原则，以及它如何在投资者与国家之间的争端解决中为国家辩护。它还对CMS v Argentina案中的《废止决定》进行了分析，以阐明必要性原则。