The article is devoted to the issues of legal regulation and mechanisms for the implementation of the powers of the Seimas of the Republic of Lithuania in the field of foreign policy. It provides a detailed analysis of the constitutional powers of the Lithuanian Parliament in exercising its foreign policy function. Special attention is paid to the analysis of the Constitutional Acts «On the Non-Alignment of the Republic of Lithuania with Post-Soviet Eastern Alliances» (1992) and «On the Membership of the Republic of Lithuania in the European Union» (2004). It is stated that the Constitutional Act of 1992 laid the foundation for the European and Euro-integration course of the Republic of Lithuania. In turn, the Constitutional Act of 2004 defined the fundamental principles of interaction between the Republic of Lithuania and the European Union. The article also mentions the important Law on Restrictive Measures in Lithuania (2023), which introduced sanctions and restrictions against certain civil rights of citizens of the aggressor states – Russia and Belarus. It is established that the core power in the exercise of the foreign policy function is the authority of the Seimas of the Republic of Lithuania to ratify and denounce international treaties. It is demonstrated that Lithuania has developed a legal framework that allows for effective parliamentary oversight over the government’s foreign policy activities. The article separately analyzes the powers of the Committee on Foreign Affairs, as defined by the Statute of the Seimas, as well as the legal regulation of the activities of international parliamentary organizations and Seimas groups on inter-parliamentary relations. It is proven that the Seimas of the Republic of Lithuania has a significant impact on foreign policy, and that the powers enshrined in the Constitution regarding the foreign policy role of the Parliament are further developed in specific laws and are thoroughly regulated by the Statute of the Seimas. The article emphasizes that for Ukraine, the experience of the Lithuanian Parliament’s functioning in the field of foreign policy is particularly valuable, considering its status as a candidate for EU membership and the necessity of post-war constitutional reform.
M.O. Khmil (Sun,) studied this question.