This article provides insufficient context for those unfamiliar with the subject.July 2018) (Learn how and when to remove this template message)(
This article is missing information about pre-21st century history of relations between these two nations.July 2018)(
Relations between Eritrea and Ethiopia are historically adversarial. Immediately after Eritrea's independence from Ethiopia in 1993, relations were cordial despite the former relationship. Since independence Eritrea's relationship with Ethiopia was entirely political, especially in the resuscitation and expansion of IGAD's scope. Since 1998 and the Eritrean–Ethiopian War, the relationship became increasingly hostile. Ties were reestablished on 9 July 2018 leading to new improved relations.
In December 2000, Eritrea and Ethiopia signed a peace treaty ending their war and created a pair of binding judicial commissions, the Eritrea-Ethiopia Border Commission and the Eritrean-Ethiopian Claims Commission, to rule on their disputed border and related claims. On April 2002 The Commission released its decision (with a clarification in 2003). Disagreements following the war have resulted in stalemate punctuated by periods of elevated tension and renewed threats of war. Since these decisions Ethiopia has refused to permit the physical demarcation of the border while Eritrea insists the border must be demarcated as defined by the Commission. Consequently, the Boundary Commission ruled boundary as virtually demarcated and effective.
Eritrea maintains a military force on its border with Ethiopia roughly equal in size to Ethiopia's force, which has required a general mobilization of a significant portion of the population. Eritrea has viewed this border dispute as an existential threat to itself in particular and the African Union in general, because it deals with the supremacy of colonial boundaries in Africa. Since the border conflict Ethiopia no longer uses Eritrean ports for its trade.
During the border conflict and since, Ethiopia has fostered militants against Eritrea (including ethnic separatists and religiously based organizations). Eritrea has retaliated by hosting militant groups against Ethiopia as well. The United Nations Security Council argues that Eritrea and Ethiopia have expanded their dispute to a second theater, Somalia.
On March 2012, Ethiopia attacked Eritrean army outposts along the border. Addis Ababa said the assault was in retaliation for the training and support given by Asmara to subversives while Eritrea said the U.S knew of the attacks, an accusation denied by US officials.
At a summit on July 8, 2018 in Asmara, Eritrea's President Isaias Afewerki and Ethiopia's Prime Minister Abiy Ahmed pledged to restore diplomatic relations and open their borders to each other. The next day, they signed a joint declaration formally ending the Eritrean–Ethiopian border conflict. Another peace agreement was signed in Jeddah, Saudi Arabia on 16 September later that year.