ABSTRACT
Cross-border co-operation and national security have become pressing inseparable issues in international politics and academic discourse. This study explores the relationship between cross-border cooperation and national security along Northeast Nigeria and the Southern Niger Republic borders in the ECOWAS sub-region. This study pursues a twofold objective; it investigates whether the inadequate enforcement of ECOWAS free movement protocol contributed to terrorist activities along Northeast Nigeria and Southern Niger Republic border. Secondly, it examines whether the weak enforcement of trans-border security agreement between Nigeria and Niger account for the proliferation of small arms and light weapon along Northeast Nigeria and Southern Niger republic borders. The study employed the qualitative method of data collection and the qualitative descriptive method of data analysis. The time series research design was used to demonstrate structural causality in the relationship between the independent and dependent variables. Utilizing the theory of neo-functionalism, the study finds that the inadequate enforcement of ECOWAS free movement protocol contributed to terrorist activities in Nigeria and Niger. Secondly, it concludes that the weak enforcement of trans-border security agreement between Nigeria and Niger account for the proliferation of small arms and light weapons along Northeast Nigeria and Southern Niger republic borders. It recommends that the key stakeholders, especially the signatories to the ECOWAS Treaty, among others, should fashion and implement an all-inclusive security policy that would address the structural and economic disarticulation in these riparian states which accounted for the sustainment of terrorist and criminal activities.