Comparative analysis of international cooperation between the State Border Guard Service of Ukraine and border agencies of neighboring states in the field of border security before and after the full-scale Russian invasion

The article examines the transformation of the mechanisms of international cooperation of the State Border Service of Ukraine with the border agencies of neighboring states and the FRONTEX agency under martial law after the full-scale invasion of the Russian Federation on February 24, 2022. The regulatory framework of international cooperation of the State Border Service of Ukraine and the main areas of interaction with the border agencies of neighboring states before and after the war are analyzed. It is established that until 2022, cooperation was based on a multilateral approach (information exchange, joint patrols, training, agreements on local border traffic). New military, hybrid and cross-border threats on the state border of Ukraine as a result of Russian aggression are identified. Specific measures introduced on the border of Ukraine are studied: simplification of refugee transit regimes, opening of temporary registration points, priority passage of humanitarian cargo, activation of joint patrols, intensification of the exchange of operational information. The complete cessation of border cooperation with Belarus was noted. The evolution of cooperation between the State Border Service of Ukraine and the FRONTEX agency was analyzed, which after February 24, 2022 moved from mainly technical assistance to active operational interaction, including the deployment of FRONTEX personnel at the borders of Ukraine with the EU countries, the provision of humanitarian and extended technical support. The effectiveness of this cooperation was assessed in terms of reducing waiting times at the border, increasing the level of exchange of experience, and ensuring the safe departure of vulnerable categories of the population. It is proven that martial law has necessitated the rapid transformation of the mechanisms of interaction between the State Border Service of Ukraine and international partners, focusing it on practical tasks: ensuring the passage of refugees, organizing humanitarian corridors, simplifying procedures for humanitarian cargo, joint counteraction to smuggling and illegal migration. The results of the study can be used to improve mechanisms of international cooperation in the field of border security under martial law.