The article is devoted to the relevant issues of international relations in the Maghreb subregion, which became especially acute after the rupture of diplomatic relations between Algeria and Morocco in August 2021. The authors analyze the general parameters of the Maghreb subsystem of international relations and identify key trends in the internal political development of its member states. The growing tension in the bilateral relations between Algeria and Morocco is only a symptom of the general crisis of the regional subsystem. The study is based on the analysis of a wide array of information and analytical materials and documents, as well as the authors’ field research in the border regions of Morocco (2019) and Algeria (2018, 2019) and interviews with Maghreb politicians (2020, 2021). The first part of the article highlights the key parameters of the Maghreb subsystem, describes its internal architecture, reveals the interconnections with other regional subsystems, and identifies the development trends of the Maghreb that took shape in the 2010s. The second part analyzes the internal political dynamics in Libya, Tunisia and Algeria. The current situation in each country can be described as an impasse, both in terms of the development of the democratic process and the possibilities for national consolidation on an authoritarian basis. The political elites of the region are unable to offer realistic strategies for state development and it leads to the growing alienation of societies. The third part of the article reveals the implications of political development crises for the regional relations. The authors conclude by putting forward a scenario of a partial reorientation of a number of Maghreb states from a deeper Mediterranean integration to finding other allies. They also identify prospects for rebalancing relations of Maghreb states with their Arab partners. In the framework of these processes the elites can use conflicting foreign policy agenda for the national consolidation of some countries. Finally, the authors raise the question of seeking new models of state and regional development in the Maghreb.