Crisis Group warns Ethiopia and Eritrea edging toward direct war

Africa | 12 October 2026 | 11 minutes

Addis Ababa and Asmara are edging closer to a direct conflict, which would cause further mayhem in the troubled Horn of Africa and the Red Sea basin. It is not too late to avert disaster.

Related Tags: Ethiopia, Eritrea, Horn of Africa

Ethiopia and Eritrea stand perilously close to all-out war as heavy fighting inches close to their shared border. The threat of resurgent interstate conflict in the Horn of Africa follows several weeks of fighting between Ethiopia's federal government and the Tigray People's Liberation Front (TPLF), which launched an armed rebellion on 23 September. The Ethiopian military has gained the upper hand in those clashes, moving northward after capturing Tigray's regional capital, Mekelle, on 3 October.

Ethiopia has accused Eritrea of supporting the TPLF and deploying military personnel on its soil, a claim that has been backed up by media reports and other accounts, though it appears that Eritrea subsequently pulled its troops back toward the border in the face of an Ethiopian advance and reported drone strikes on its forces. The effects of these cross-border movements could be dire: they could trigger a full-scale war between Ethiopia and Eritrea that, in turn, could spiral into a wider conflagration along Eritrea's Red Sea coast. A push at the highest political and diplomatic levels to prevent this budding confrontation is a matter of extreme urgency.

The Resurgence of Conflict

The risk of direct conflict between Ethiopia and Eritrea has risen sharply since late September as war has engulfed Tigray. On 20 September, the TPLF and six other groups announced a new "alliance for survival" aimed at toppling Prime Minister Abiy Ahmed's government, which they see as authoritarian and bent on centralising power. Two days later, Ethiopia conducted a large drone raid on sites in southern Tigray, where officials believed the TPLF was massing for an attack. On 23 September, the TPLF mounted large-scale offensives against the federal government. It was apparently trying to join forces with two of its allies, the Amhara Fano and Afar Revolutionary Democratic Unity Front, which commenced their own assaults on Ethiopian military positions near Tigray's boundaries.

This first wave of attacks made gains, but Ethiopian forces quickly regrouped. They have steadily pushed the Tigrayans back since then, recording a string of battlefield victories and capturing most of Tigray. On 3 October, federal forces and their allies took Mekelle without a fight. As the TPLF withdrew, the war's front line shifted toward the group's strongholds in the northern mountains, near the border with Eritrea. At the same time, tensions between Ethiopia and Eritrea reached fever pitch in the wake of reported Eritrean troop deployments to northern Tigray in support of the TPLF's rear guard.

For the first time since 2000, when Ethiopia and Eritrea ended their last war, the two neighbours now seem poised to engage in frontal combat.

Frictions between the two are neither sudden nor surprising, even if the present rift between them in some ways marks a radical turnaround. For more than a year, Addis Ababa has been denouncing Asmara, and more recently its allies in the Sudanese army, for backing rebel groups in Ethiopia, particularly the TPLF. This antagonism stands in sharp contrast to what prevailed during the last Tigray war, which raged between 2020 and 2022, when Ethiopia and Eritrea had become friends rather than foes.

That conflict came on the heels of Abiy's ascent to power, which in turn dethroned the TPLF, a pivotal force in national politics for decades, and set the stage for a power struggle between the federal government and the TPLF high command in Tigray. Eritrea, which had fought its previous war with Ethiopia from 1998 to 2000 while the TPLF was in charge in Addis Ababa, sought common cause with Abiy in confronting the group after Tigrayan forces attacked Ethiopia's Northern Command in November 2020. A seesaw battle ensued, with Addis Ababa and its allies eventually beating back the TPLF ahead of the signing of the Pretoria peace agreement in November 2022.

This agreement left the TPLF largely intact, however, and its commitment to fully demobilise its armed forces was never fully enforced. Eritrea, which was not involved in the Pretoria negotiations, had been pushing for the group's complete elimination. Asmara was incensed at the outcome. In its view, its critical national interests had not been respected during the talks. Eritrea's relations with Ethiopia subsequently began to deteriorate.

Some say Abiy was quietly courting the TPLF in order to establish a new alliance with it against Eritrea in the acrimonious aftermath of the peace deal. TPLF leaders apparently rebuffed these advances. Abiy also began to argue in public that Ethiopia needed to restore sovereign access to the sea. He said Ethiopia had a historical claim to the Red Sea coastline, which it had lost when Eritrea seceded in 1993. Since then, Ethiopia, the world's largest landlocked country by population size, has been relying almost exclusively on Djibouti to export goods by sea. Officials in Abiy's government have stressed that Ethiopia will not be satisfied merely with access to a wider range of ports, a course some have suggested it pursue, but needs a sovereign seaboard with a naval base. Asmara has viewed this rhetoric as a threat to seize Eritrea's coastline, especially its southern port of Assab, by armed force.

With bilateral relations souring, Eritrea and the TPLF began to explore establishing a common front against Addis Ababa.

Asmara appears to have seen Tigray in the TPLF's grip as a potential geographic buffer between it and the Ethiopian heartland, as well as a military counterweight to Addis Ababa. The TPLF, for its part, was keen to break the encirclement it endured in the 2020-2022 war. As a sign of their strengthening ties, Eritrean and Tigrayan authorities promoted new cross-border "people-to-people" exchanges known as tsimdo ("engagement" in Tigrinya), providing further ballast for their switch from adversaries to allies.

Meanwhile, the 2022 peace deal began to fray. The TPLF complained that the government had failed to resolve major issues stemming from the conflict, including the status of disputed territories occupied by Amhara forces during the war and the return of displaced people to their homes in these areas. Little effort was made to remedy the antipathy between the TPLF and Abiy: Addis Ababa never reintegrated Tigray back into the national political federation, with the region remaining without representation in parliament or other institutions in the capital.

In March 2025, the TPLF ousted the first post-war interim Tigray administrator, Getachew Reda, who had been a lead negotiator in the Pretoria peace negotiations for the TPLF and was chosen ahead of TPLF chairperson Debretsion Gebremichael. The group claimed that Getachew was too close to the federal government and had not defended Tigray's interests sufficiently during his time in office. (Getachew fled to Addis Ababa, where he joined Abiy's administration.) Abiy then appointed Tadesse Werede, a top Tigrayan general, in Getachew's place, but the relationship between Tigray's new ruler and the TPLF also began to worsen.

In May 2026, the TPLF retook power in Mekelle, dismantling the interim administration, reinstalling its leader Debretsion as regional president and placing Tadesse under house arrest. The federal government responded by tightening its economic restrictions on the region and launching a campaign of airstrikes inside Tigray. In August, a major clash broke out between TPLF and federal ground forces before quickly subsiding. Shuttle diplomacy by the African Union and others aimed at restarting negotiations failed to gain traction.

Simultaneously, mediators found their efforts thwarted by rising hostility among powers across the Horn. Addis Ababa began to denounce Asmara for trying to coordinate a transnational alliance against it, and accused the Sudanese army, an ally of Eritrea and Egypt (another Ethiopian foe), of supporting meetings of a nascent alliance of opposition groups in eastern Sudan. Ethiopia also complained that Sudan was harbouring a group of Tigrayan troops, known as Army 70, in Sudanese territory, where they were said to have stood alongside the army in fighting its enemy, the Rapid Support Forces (RSF). Ethiopia, on the other hand, began allowing the RSF to base itself in its Benishangul-Gumuz region close to the Sudanese border, from where it could launch attacks into Sudan's Blue Nile state. Ethiopia's relations with the Sudanese army, which had continued to function despite the chill between them, became icy as a result. Sudan has also claimed that drones attacking Khartoum were dispatched from Ethiopian territory.

Neighbours at Loggerheads

This mosaic of enmities and alliances has come into sharp relief since war broke out in Tigray. As hostilities have intensified, Ethiopia and Eritrea have edged ever closer to conflict. Ethiopia considers Eritrea to be masterminding the TPLF's war effort. Soon after fighting broke out, Ethiopian federal officials and Afar's regional president accused Eritrea of deploying forces in the Afar region. On 1 October, Ethiopia expelled all Eritrean diplomats from the country, accusing Asmara of "direct and indirect acts of hostility and belligerence". All diplomatic ties between the two states have since been severed.

After Ethiopian federal forces began advancing north of Mekelle, the first reports emerged of alleged Eritrean deployments in northern Tigray, seemingly with the aim of bolstering the TPLF's defensive lines. Several media reports indicated on 7 October that Eritrean units had passed through Adigrat, 30km south of the Ethiopian border. Accounts also suggest that Eritrean forces took up positions south of Adigrat in the Edaga Hamus area. A day later, after reported drone strikes on Eritrean vehicles, some of its forces reportedly withdrew to the border. With Ethiopian forces currently approaching the frontier at several points, the two armies are positioned in alarmingly close proximity.

Asmara's apparent gamble to intervene more directly in the war, even if the incursion was brief, could well backfire. On 9 October, Ethiopia wrote a letter to the UN Security Council saying it was "taking measures" of self-defence in response to Eritrea's deployment of infantry and mechanised units across the border and occupation of Ethiopian territory. The letter also accused Eritrea of "harbouring, supporting, financing, arming and directing armed insurgent groups operating within Ethiopia". On 10 October, Eritrea responded with its own letter, accusing Ethiopia of declaring a "war of aggression" against it three years ago and using self-defence as a pretext for acts of war. The Security Council has scheduled a closed-door session to discuss the crisis on 13 October.

A standoff along the two countries' frontier would be an ominous turn of events.

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