A diplomatic incident, hardening political positions and a fractured regional security architecture are deepening the rift between Nigeria and its three Sahelian neighbours — Burkina Faso, Mali and Niger — even as the armed groups threatening all four countries continue to operate without regard for borders.
The tensions came into sharp focus in December 2025, when Burkina Faso detained 11 Nigerian Air Force personnel after their C-130 transport aircraft made an emergency landing in Bobo-Dioulasso, a city in the country's southwest, while en route to Portugal for maintenance. Burkina Faso said the aircraft had entered its airspace without authorisation; Nigeria said the landing was a precautionary response to a technical fault and fully in line with aviation safety procedures. The crew was released after diplomatic talks and departed on December 19. The episode was one in a series of flashpoints that have steadily hardened positions between Abuja and the capitals of the three countries that now form the Alliance of Sahel States (AES) — a collective defence framework established in September 2023 under the Liptako-Gourma Charter, named for the tri-border region where Mali, Burkina Faso and Niger converge. The three states formally withdrew from ECOWAS, the 15-member West African regional bloc, on January 29, 2025.
The political rupture is unfolding against a deteriorating security landscape. Boko Haram and the Islamic State in West Africa Province (ISWAP) remain active in Nigeria's northeast, and ISWAP also operates in southeastern Niger, particularly around the Diffa region near the Lake Chad Basin. Niger's decision in March 2025 to withdraw from the Multinational Joint Task Force — a regional military mechanism established to combat armed groups around Lake Chad — has left a significant gap in cross-border counterterrorism coordination, according to security analysts. Meanwhile, in late April 2026, coordinated attacks struck multiple sites in Mali, killing Defence Minister Sadio Camara in Kati, near the capital Bamako. The attacks were jointly claimed by al-Qaeda-linked Jamaat Nusrat al-Islam wal-Muslimin (JNIM) and the Tuareg-led Azawad Liberation Front — a rare convergence of groups with differing objectives, underlining the volatile nature of the threat. Bolaji Akinyemi, a former Nigerian foreign minister, traces part of the region's instability to the 2011 collapse of Muammar Gaddafi's government in Libya, which he says drove armed actors southward into the Sahel and eventually into northern Nigeria.
The political fallout has also added uncertainty to trade and migration. Nigeria is West Africa's largest economy and a vital market for goods moving along the Sahel corridor. ECOWAS has said that citizens of the three AES states will continue to enjoy visa-free movement within the bloc for the time being, and that existing trade arrangements will be maintained. But traders and transport operators remain uncertain about the longer-term rules governing cross-border commerce. A Malian analyst told Al Jazeera that each new confrontation — from threatened sanctions in 2023 to the aircraft detention in December 2025 to an exchange of public recriminations over cross-border insecurity in mid-2026 — has entrenched rather than softened positions on all sides.
Why this matters: armed groups such as JNIM and ISWAP do not recognise the political frontiers separating Nigeria from its neighbours, and a breakdown in regional security cooperation creates openings they have historically exploited. Against this backdrop, interfaith and civil society initiatives are also seeking to address the social dimensions of the crisis. Under the patronage of Nigerian President Bola Tinubu, the Muslim World League convened a conference in Abuja bringing together Muslim and Christian leaders, government officials and civil society representatives, resulting in the Abuja Declaration — a commitment to strengthen interfaith dialogue and conflict prevention across West Africa. Analysts warn, however, that unless Nigeria and the AES states find durable diplomatic channels capable of surviving their political disagreements, West Africa risks consolidating into two parallel security architectures that do not communicate with each other, even as the threats they face grow more transnational by the month.