Ethiopia expelled ten Eritrean diplomats on Thursday and closed its embassy in Asmara. Eritrea answered that it would sever all diplomatic ties. Two governments that fought a border war, then made a peace that won Abiy Ahmed a Nobel Prize, are formally estranged again.
The stated cause is Tigray. Ethiopian military officials accuse Eritrea of backing the TPLF-led alliance that resumed fighting in September. Eritrea denies it.
That accusation is worth pausing on, because it inverts the last war. In 2020 Eritrean troops entered Tigray alongside Ethiopian federal forces, against the TPLF. The claim now is that Asmara has switched to the other side of the same conflict. Neither we nor, as far as we can establish, any news organisation has produced evidence for it.
Egypt, within the same week
Ethiopia also expelled an Egyptian diplomat, without explanation. Cairo expelled an Ethiopian counsellor in return. The two countries were already at odds over Ethiopia's new Nile mega-dam, and AFP reports that Egypt has been strengthening its ties with Eritrea in recent months.
Ethiopian military officials have named Eritrea, Egypt and Sudan together as supporters of the alliance. Egypt and Eritrea both deny trying to destabilise Ethiopia. The African Union says it is following the tensions with concern and has urged all three to show maximum restraint.
What this is actually about
The quarrel is older than this war, and it is geographic.
Ethiopia is landlocked and has said openly that it wants access to a port. Eritrea holds the coastline, and has long feared that Ethiopia intends to take it. Egypt's concern is water: a dam upstream on a river it depends on completely.
The TPLF's own leader put it in those terms. In a video published late on Thursday, Debretsion Gebremichael said the war "is regional and it is a war to control the Red Sea" — a striking framing from a man whose forces are fighting several hundred kilometres inland.
What to watch
Expulsions are cheap. They are the gesture states reach for when they want to register anger without doing anything irreversible, and they are frequently reversed.
The thing that would change the picture is Eritrean troops moving. That would turn a civil war into an interstate one, and it is also the development we are least equipped to catch early: the border region is remote, communications across Tigray are down, and journalists are being kept out.