The Relationship between the United Nations Space Treaties and the Vienna Convention on the Law of Treaties

A review of the United Nations Space Treaties from the perspective of the 1969 Vienna Convention on the Law of Treaties (VCLT) is both a very interesting academic exercise and an extremely difficult and complex proposition. This issue has so far not been fully addressed in space law literature, but it is clear that general public international law principles relating to treaties are relevant to the international regulation of outer space. Since there are several difficult issues involved in determining the precise nature of the relationship between the United Nations Space Treaties and the principles set out in the VCLT, this paper seeks to analyze certain treaty rules (both within the VCLT and/or under customary international law) to ascertain their relevance to the international treaty law relating to the exploration and use of outer space. In this way, it is hoped thar this paper will clarify some of the more pressing and practical issues, including those that relate to: the obligations of signatories, the interpretation of the United Nations Space Treaties, the fulfilment of international obligations in good faith and the consequences of their non-fulfillment, the creation of rights and obligations for third States, the effect of a jus cogeus norm, and situations amounting to a fundamemal change in circumstances.