After five years of closure local activists and community leaders reopened a border post to Eritrea, in the town of Zalambessa. This seemingly positive development from Ethiopia’s Tigray region might seem like a hopeful sign at first glance, but tells only part of the story. The Tigray People’s Liberation Front (TPLF) and Eritrea have improved relations through a makeshift alliance with the aim of facing Ethiopia in a potential military escalation. Previously, the 2020-2022 Tigray war saw the Ethiopian federal government and Eritrean regime fighting against the TPLF. So, this new and unthinkable Eritrea-TPLF alliance should raise concerns about what lies ahead.

The relationship between the TPLF and Eritrea’s leadership has experienced numerous fluctuations, tracing back to their origins as liberation movements in the 1970s and 1980s. The TPLF and Eritrean People’s Liberation Front (EPLF) initially supported each other in overthrowing the Mengistu regime in Ethiopia and achieving Eritrea’s independence. After victory in 1991, the group’s leaders assumed state power and initially maintained an amicable relationship. However, the tide turned in 1998 when a two-year border war erupted, transforming the TPLF-Eritrea relationship into one of enmity.

After 25 years of continuous hostilities and open conflict between the Eritrean regime and the TPLF, the inconceivable has happened over the past months. After power struggles in Tigray, the Eritrean regime has positioned itself as an ally to a TPLF faction, led by its chairperson, Debretsion Gebremichael. The TPLF’s once unified leadership has fractured and is split between Debretsion and Getachew Reda, who served as the head of the federally backed Tigray Interim Administration, a postwar apparatus, until March 2025. Getachew was subsequently appointed as advisor in the federal government and registered a new political party approved by the national election board. Meanwhile, the TPLF is being denied its status as a political party by Ethiopian authorities.

Amidst these developments in Tigray, Eritrea successfully inserted itself into the showdown as TPLF’s unlikely ally, embracing the logic of “the enemy of my enemy is my friend.” This strategy is not new for Eritrea’s leadership. It also informed Eritrea’s 2018 peace deal with Ethiopia’s then newly appointed prime minister, Abiy Ahmed Ali, which ended the hostile political relationship between the two countries. Prior to the deal, any rapprochement and even cordial relations between the two states were completely off the table.

The peace deal quickly took a darker turn, revealing the Ethiopia-Eritrea friendship pact as a ruthless war coalition in the Tigray war. A feud erupted between Tigray’s regional administration, under the TPLF, and Ethiopia’s federal government. The government in Addis Ababa deemed the 2020 regional election in Tigray illegal. This political standoff rapidly escalated into military confrontation, eventually spiraling into a full-scale war that lasted two years. During the conflict, Eritrean forces joined the Ethiopian military in coordinated operations against the TPLF and Tigrayan civilians. A June 2025 investigation by The Sentry details the systematic looting by Eritrean forces in addition to widespread atrocities and grave human rights violations against civilians in Tigray.

The postwar constellation of actors has created a series of unintended ripple effects in the region. The 2022 Pretoria Agreement ended the war between Ethiopia’s federal government and the TPLF but was limited. It excluded the Eritrean regime, fighting alongside Ethiopia, as a party to the conflict, even though their soldiers remained in contested areas of Tigray long after the war’s end. Ethiopia’s federal government has been emboldened by the agreement, which hastened the downfall of the TPLF, a party that had long wielded influence on the federal level. Consequently, Ethiopia’s expansionist ambitions have been reignited. They have demanded sea access as their natural right, which has fueled regional tensions with Somalia and Eritrea. While escalation with Somalia was averted in late 2024 through mediation by Turkey, observers have warned that war between Ethiopia and Eritrea alongside the TPLF might be impending.

The situation in 2025 has striking similarities to early 2020, albeit with new relationship dynamics, and now with the opportunity to avert violent escalation. Leaders in Asmara, Addis Ababa, or Mekelle are not keen to launch another war. They all have thinly stretched resources, and Ethiopia must manage various violent flash points, including in the Amhara and Oromia regions undermining its assertive rhetoric on sea access. In February 2025, Eritrea had ordered a nationwide mobilization; however, little information about the current state of the Eritrean army, which is largely composed of conscripts, is available. The TPLF’s stronghold in Tigray is challenged and lacks the unity and strength it exhibited during the Tigray war.

A cascade of escalatory statements and unexpected events can quickly tip the uneasy equilibrium towards military confrontation, especially considering the upcoming 2026 federal elections in Ethiopia. It will be crucial to continue monitoring the statements and behaviors of senior officials from all sides. The power struggle in Tigray and Eritrea’s rapprochement with its former enemy serve as early warning signs. They demand preventative diplomatic measures to de-escalate and to avoid military confrontation with Ethiopia. Diplomatic engagement with Ethiopia and Eritrea by mediators (such as Turkey or Saudi Arabia) with interests in the region’s stability is required to defuse tensions. Both countries have  been previously engaged as brokers: Turkey in the 2024 Somalia-Ethiopia tensions and Saudi Arabia in the 2018 peace deal between Eritrea and Ethiopia. The new US focus on “dealmaking” might serve as a model for them and can incentivize these potential mediators to secure their economic interests by promoting mediation.

Should these efforts fail, and tensions escalate into boots on the ground, coercive measures should be pursued. For instance, new US and EU sanctions can target Ethiopian and Eritrean senior leadership. Similarly, there could be further efforts to curb Eritrea’s informal financial networks by investigating financial flows in the diaspora and pursuing prosecution for illegal actions. Eritrea is likely to exploit international attention and resources being increasingly diverted from the Horn of Africa by Europe and the US. Eritrea’s leadership has previously used such attention vacuums, notably in the aftermath of 9/11, when it arrested leading political opponents and consolidated its totalitarian grip.

Ethiopia today might be labeled as a post-conflict context; yet its recent history serves as a cautionary tale, revealing how quickly so-called peace can unravel. Eritrea, a pariah state and a daunting diplomatic challenge, remains a dangerous spoiler in the region. The Horn of Africa is already on the verge of collapse, therefore diplomatic de-escalation and sanctions to curb expansionist ambition and spoilers are crucial.