The dissertation research provides a theoretical generalization and contains a new solution to the scientific problem, which is to highlight the features of the mechanism of financial and legal regulation of payment systems in Ukraine after the adoption and introduction of new legislation on payment services.
In the dissertation, based on the analysis and generalization of scientific works and normative legal acts, a new approach to the consideration of the concept of "payment system" as a kind of legal form is proposed, the content of which is highlighted through its constituent elements, and the essence is revealed using the designation of the main function-the provision of payment services. Taking into account the significant update of the national legislation of Ukraine in the field of providing payment services, it is indicated that the emphasis in understanding the essence of the concept of "payment system" is on transferring funds (as it was before) to perform payment operations (a new approach). It is emphasized that the term "payment services" is broader in meaning in relation to the related concepts of "payment operations" and "transfer of funds".
The definition of the payment system as a personalized organizational and legal form of activity for the provision of payment services is formulated in the context of identifying payment infrastructure entities.
During the consideration of the classification of payment systems, it is proposed to divide them according to such a legal criterion as the state legitimation of payment services into: 1) systems of alternative (unregulated, unofficial, illegal, informal, traditional, etc.) money transfers that have different names, forms of manifestation and mechanisms of functioning, and, 2) payment systems whose creation is associated with the state, its founding, organizational and regulatory functions, which find their manifestation in the formation and administration of payment infrastructure that meets the needs of Public Finance.
The author's idea of periodization of legal regulation of payment systems in Ukraine is outlined. It is pointed out the dual nature of the current stage of legal regulation of the payment market sphere, when on the one hand the implementation of the course towards European integration continues consistently, the deepening of the adaptation of the national model of payment services to the requirements of the EU acquis and international standards, and on the other hand, the legislation is being adjusted in accordance with the conditions of martial law. A forecast was made regarding the specifics of the next stage of legal regulation of payment systems in Ukraine, the essence of which will be to cancel the imposed restrictions on the operation of payment systems after the end of the martial law regime and the introduction of a transition period to adapt national payment services to their functioning as part of the single euro payment zone (SEPA) in peacetime in accordance with international standards and post-war economic conditions.
A scientific approach is applied to the coverage of the peculiarities of legal regulation of payment systems from the standpoint of the financial and Legal Institute of monetary circulation, and arguments are given against the doctrinal concepts of a separate legal institution of payment systems or a sub-branch of banking law - payment law due to their discussion and insufficient validity.
The author's definition of the concept of the mechanism of financial and legal regulation of payment systems as a set of interrelated legal means by which a stable ordering of public relations in the sphere of providing payment services is ensured, which establishes the legal status of their subjects, reveals the legal nature and outlines the range of rights and obligations of such persons, defines the types and conditions of legal liability as a tool for preventing the commission of relevant offenses.
A general description of the mechanism of financial and legal regulation of payment systems is given, which is characterized by the application of all possible types of legal norms, which indicates both its instrumental complexity and the flexibility of the means used.
Participants in legal relations related to the organization and functioning of payment systems are divided into: 1) subjects of payment legal relations (subjects of legal relations in the payment system) and, 2) subjects that are tangent to such legal relations (bodies that carry out legal regulation of such relations and implement the functions of their administration, including control ones).
