The aim of the study is to examine the importance of economic argumentation in international maritime disputes. The paper first explains what the international maritime disputes, their sources and types are, what principles they are subjected to. It also established what should be understood by economic arguments, emphasizing their relative nature, as well as showing the potential of the Convention on the Law of the Sea of 1982 as a basis for formulating economic argumentation. The importance of economic argumentation was considered in relation to international disputes regarding the legal status of maritime territories, delimitation of maritime zones, power over the sea and use of the sea.

Research, carried out, leads to the following conclusions: 1) economic arguments are present in the reasoning of the parties as well as dispute settlement bodies. However, their probative value is limited; 2) in disputes related to the status of maritime features economic reasoning appears in the context of necessity to demonstrate that they can be a basis for delimitation; 3) in delimitation disputes, addressing economic arguments is more complex and contradictory. Economic arguments may be useful in the second phase of delimitation when relevant circumstances are considered. However, the existing practice shows that the range of economic arguments is limited (they cannot serve as a reason for correction of natural inequalities). International jurisprudence denies taking into account arguments based on level of economic development or economic or financial difficulties of a state (except for the catastrophic repercussions for the livelihood and economic wellbeing of the population), the needs of economic development or performance of economic activities (mining, fishing, shipping). An argument associated with assurance of deposit unity is of some importance (when resources are known or readily ascertainable); 4) in disputes concerning the power over the sea some weight is held by an argument associated with the establishment of economic authority, in particular, of a regulatory and control nature; 5) in disputes related to the use of the sea, the importance of economic reasoning is varied. In disputes concerning the prompt release, the role of the economic argument is limited. On the contrary, it is relevant in disputes related to the violation of rights and economic interests of States and people, if they are protected by international law.

The article concerns the obligations to negotiate and conclude agreements in good faith (pactum de negotiando and pactum de contrahendo), which are used in international legal practice to more efficiently settle disputes or negotiate new agreements in various areas of international law. These obligations, however, are sometimes mixed together and misunderstood. They also give rise to various interpretation disputes related to their existence as obligations and their content. The aim of the study is to show that these are not simple obligations, but bundles of obligations. Such perception of them makes it possible to distinguish both pacta and penetrate into their rich content, as well as to unequivocally apply to their performance the principle of performing international obligations in good faith (Art. 2(2) of the UN Charter), especially in the form of pacta sunt servanda (Art. 26 of the Vienna Convention on the Law of Treaties).