Supervening Impossibility of Performance and the Effect of Armed Conflict on Investment Treaties: Any Room for Manoeuvre?

The protection of foreign investments in areas torn by armed conflicts has become a pressing concern following the recent outbreak of hostilities in several regions of the world. This chapter addresses the specific question of whether there is any space (and how much of it) for a host State to successfully invoke the doctrine or principle of supervening impossibility of performance in respect of international investment agreements when an armed conflict emerges. International law tribunals and doctrine have generally adopted a very strict stance on the subject, almost totally depriving this doctrine of any practical significance. Article 61 of the Vienna Convention on the Law of Treaties, which is considered to reflect customary international law, and which requires the permanent disappearance or destruction of an object indispensable for the execution of the treaty, has also been taken to establish a very exacting test for any successful invocation of this principle. Once the principle is placed in the context of armed conflicts and international investment agreements, one might also question whether an investment agreement is suspended or terminated as a consequence of hostilities and whether the principle can be invoked with specific regard to investment agreements. This chapter addresses, in turn, all these points and argues that, though limited, there might be some space for the supervening impossibility of performance to be successfully invoked in respect of international investment agreements should an armed conflict arise. Nonetheless, from a practical point of view, the invocation of this principle might still not be the easiest course of action in particular if compared to other doctrines or principles such as force majeure and state of necessity.