Ethiopian Prime Minister Abiy Ahmed’s renewed push for “sovereign” access to the sea is sharpening fault lines across the Horn of Africa, as his public messaging increasingly points toward Eritrea’s Red Sea port of Assab territory Eritrea has controlled since independence in 1993.

For Ethiopia, the stakes are economic and strategic. The country is the world’s most populous landlocked nation, and its trade dependence on Djibouti carries major costs a pressure point Abiy has repeatedly highlighted as part of a wider national renewal agenda.

But the regional implications go far beyond logistics. Any attempt to change access arrangements through coercion or even sustained brinkmanship risks triggering a chain reaction in a neighbourhood already strained by overlapping conflicts, fragile ceasefires, and shifting alliances. Analysts warn that tensions between Addis Ababa and Asmara are rising alongside internal Ethiopian pressures, including continuing violence in Oromia and Amhara and unresolved post-war fault lines in Tigray.

The flashpoint is the Ethiopia–Eritrea border relationship itself, which has swung from hostility to détente and back again over the past decade. Abiy’s 2018 opening to Eritrean President Isaias Afwerki helped deliver the 2019 Nobel Peace Prize, but the relationship soured after Ethiopia’s Tigray war a conflict in which Eritrean forces fought alongside Ethiopian federal troops against Tigrayan authorities before a 2022 peace deal ended large-scale fighting.

Now, the same geography that made Eritrea a wartime ally has become a strategic constraint and a potential trigger. Tigray’s position along the Eritrean frontier adds a destabilising layer, because any Ethiopia–Eritrea confrontation could quickly intersect with local power struggles in northern Ethiopia, and with wider regional calculations involving neighbours and external partners.

International actors have urged restraint and respect for sovereignty, pointing to the framework designed to prevent the border dispute from spiralling into open war. In a statement marking 25 years since the Algiers Agreement the treaty that formally ended the Ethiopia–Eritrea border war UN Secretary-General António Guterres called on both sides to recommit to peaceful relations and respect territorial integrity. Read UN statement here.

For the Horn of Africa, the risk is that a dispute framed as an “existential” economic need becomes a broader security crisis: one that pulls in actors across the Red Sea corridor, disrupts trade routes, and deepens already volatile domestic politics inside Ethiopia and Eritrea. Even without a full-scale invasion, sustained military signalling, border mobilisation, or proxy-style escalation could be enough to ignite a conflict that is difficult to contain once it starts.