The article analyzes the influence of the concepts of the Intermarium and the Baltic-Black Sea Arc on the formation of Ukraine’s foreign policy in 1990 – early 2000. The use of these concepts in American, European and Ukrainian geopolitical thought, which historically included the idea of opposing Russian influence in the region, contributed to the increase in tension and was aimed at further disintegration of the Western flank of the post-Soviet space. The article proves that the design of the Euro-Atlantic vector of Ukraine’s foreign policy was already active under the first two Ukrainian presidents – Leonid Kravchuk (1991–1994) and Leonid Kuchma (1994–2005). One of the concrete attempts to implement the idea of forming a common political, economic, transport and logistics space of the Black Sea-Caspian region with a promising expansion of the cooperation zone to the whole of Eastern Europe and the Eastern Baltic during the presidency of Leonid Kuchma was the foundation and launch of a new regional organization, Organization for Democracy and Economic Development, better known as GUAM (composed by the initial letters of names of member states – Georgia, Ukraine, Azerbaijan, Moldova; when Uzbekistan was also a member of Organization for Democracy and Economic Development, the name of the organization was GUUAM), which is an alternative to Eurasian projects with the participation of Russia.