Ethiopia vs. Eritrea

Eritrea and Ethiopia agreed to abide by the 2002 Eritrea-Ethiopia Boundary Commission's (EEBC) delimitation decision, but neither party responded to the revised line detailed in the November 2006 EEBC Demarcation Statement; the undemarcated former British administrative line has little meaning as a political separation to rival clans within Ethiopia's Ogaden and southern Somalia's Oromo region; Ethiopian forces invaded southern Somalia and routed Islamist courts from Mogadishu in January 2007; "Somaliland" secessionists provide port facilities in Berbera and trade ties to landlocked Ethiopia; civil unrest in eastern Sudan has hampered efforts to demarcate the porous boundary with Ethiopia; Ethiopia's construction of a large dam (the Grand Ethiopian Renaissance Dam) on the Blue Nile since 2011 has become a focal point of relations with Egypt and Sudan; as of 2020, four years of three-way talks between the three capitals over operating the dam and filling its reservoir had made little progress; Ethiopia began filling the dam in July 2020

Eritrea and Ethiopia agreed to abide by 2002 Ethiopia-Eritrea Boundary Commission's (EEBC) delimitation decision, but neither party responded to the revised line detailed in the November 2006 EEBC Demarcation Statement; Sudan accuses Eritrea of supporting eastern Sudanese rebel groups; in 2008, Eritrean troops moved across the border on Ras Doumera peninsula and occupied Doumera Island with undefined sovereignty in the Red Sea