Which countries have stakes in Ethiopia's war?

Ethiopian troops are battling rebellious forces from the country's northern Tigray region. Fallout from the conflict in Africa's second most-populous nation is already spilling over into Ethiopia's neighbours, threatening to further destabilise a fragile region.

Eritrea - Three missiles fired by Tigrayan forces slammed into the Eritrean capital Asmara this weekend. Eritrea won its independence from Ethiopia in 1991 but the two nations went back to war over a border dispute in 1998-2000, when the Tigrayan ethnic group dominated Ethiopian politics.

Tigrayan ascendancy ended when Ethiopian Prime Minister Abiy Ahmed took power in 2018. Last year, he won the Nobel peace prize for signing a peace deal with Eritrea. Abiy's rapprochement with Eritrea angered the Tigrayan leadership and came as several high-ranking Tigrayan former officials were put on trial for abuses and corruption.

Sudan - Since fighting began in Tigray, at least 25,000 refugees have poured across the border into cash-strapped Sudan, where a joint civilian-military government is struggling to cement fragile peace deals with a plethora of armed groups. The sliver of territory next to Sudan is Tigray's only border not controlled by Ethiopian or Eritrean forces.

Also read: Escape from massacre: Ethiopians recall Tigray conflict horror

Sudan has a long-running border quarrel with Ethiopia - both sides claim the fertile Fashqa triangle - but the bigger dispute between the two nations centres on Ethiopia's giant Grand Ethiopian Renaissance Dam, which will dam the waters of the Blue Nile. Both Egypt and Sudan are concerned the $4 billion dam might threaten their water supplies.

Egypt - Egypt and Sudan are holding joint war exercises this week, scheduled long before the Tigrayan conflict broke out but intended as a joint show of force amid the unresolved dispute over Ethiopia's dam on the Nile.

Egypt, which is Africa's third-most populous nation, relies on the Nile for more than 90% of its fresh water supplies and wants a legally binding treaty on how Ethiopia can use the Bule Nile's waters.

Somalia - Ethiopian troops are in Somalia both as part of an African Union peacekeeping force and as bilateral forces. Somalia, ravaged by civil war since 1991, is battling al-Qaeda linked Islamist militant group al Shabaab, which has also carried out attacks in Ethiopia. Ethiopia shares a long and porous border with Somalia and has a large ethnically Somali population.

Djibouti - Tiny Djibouti punches well above its weight in the region because it hosts both U.S. and Chinese military bases and because its port is Ethiopia's only access to the sea. Djibouti, which borders Eritrea, Ethiopia and Somalia, has issued a statement calling for a peaceful resolution to the conflict and the opening of humanitarian corridors.