The article is devoted to issues of the integration cooperation between Russia and Belarus within the framework of the Union State in the context of external influence at the present stage. It highlights the dynamics in the matter in the period from May 2020 to October 2021. In an applied research based on the methods of event analysis, frequency and thematic content analysis, the authors systematized the external challenges and threats articulated by the member countries of the Union State that hinder RussianBelarusian integration. They revealed specifics of the reaction of key actors to external influence in the context of the internal political situation and union construction. The interest of Russia and Belarus in building mutually beneficial cooperation and deepening integration is emphasized. The authors draw their main conclusion on a recognition of the catalyzation in the Union State integration interaction in the current period. Its driver was largely the negative impulses coming from the external environment. They also contribute additional mobility and instability to the motivation of internal actors and agents. Effective prevention, suppression and minimization of emerging risks are combined with overcoming existing gaps in the internal and external dimensions of the integration process.