Ethiopia and Eritrea have been bitter enemies for decades, fighting a border war in 1998-2000 that cost nearly 80 000 lives and remains a flashpoint today.
As the two sides hold a historic meeting in the Ethiopian capital of Addis Ababa, here is an overview of their long and troubled relationship.
Eritrea breaks away
In 1962, Ethiopia’s last emperor, Haile Selassie, proclaims the annexation of Eritrea, abolishing its autonomous status and effectively making it a province.
Eritrea launches a war for independence that lasts nearly 30 years.
In 1991, Eritrean rebels, who help overthrow the military-Marxist Ethiopian regime of Colonel Mengistu Haile Mariam, seize Asmara, the Eritrean capital. They install a government, gaining de facto independence.
Eritrea gains full independence in May 1993, a secession blessed by Addis Ababa.
However, the 1 000-kilometre border between the neighbours is not properly defined and the move deprives Ethiopia of its only entry point to the Red Sea.
In May 1998, the first skirmishes erupt between the Eritrean and Ethiopian forces. Eritrean forces enter the area around the town of Badme, claiming it is part of its territory according to borders dating to Italian colonial rule.
Fighting spreads and in June the warring sides carry out air strikes.
The ensuring conflict is marked by trench warfare and large-scale pitched battles, punctuated by long periods of calm. Attempts at mediation fail.
Fighting flares anew in May 2000. A fierce bombardment of Eritrea turns the conflict in favour of Ethiopia, while indirect negotiations resume in Algiers.
Peace deal reached
In June 2000 the two sides reach an initial peace accord brokered by the Organisation of African Unity (OAU).
It allows for the deployment of a UN peacekeeping force in a buffer zone along the border and calls for the withdrawal of Ethiopian troops from areas deep inside Eritrea.
The leaders of the neighbours sign an official peace pact in December 2000.
It establishes a Boundary Commission, an international body that sits at the International Court of Arbitration in The Hague, to officially demarcate the disputed frontier. Its ruling is to be “final and binding”.
In April 2002 the commission delivers its decision, notably attributing to Eritrea the contested town of Badme, a particular hotspot even though it lies in sparsely populated, rocky terrain and has no strategic or economic significance.
Ethiopia rejects the ruling as “illegal, unjust and irresponsible” and requests an “interpretation, correction and consultation”. The commission refuses.
The standoff holds up the physical demarcation of the border in terms of the commission’s ruling.
Tensions rise between the two sides with gunfire, landmines and troop movements near the border.
In December 2005, the Eritrea Ethiopia Claims Commission (EECC) rules meanwhile that Eritrea violated international law when it invaded Badme in 1998, at the start of the conflict. Eritrea reluctantly accepts.
In May 2006, amid fears of a new all-out war, talks are held in London on resuming the demarcation of the border but fail, the neighbours accusing each other of holding to longstanding inflexible positions.
In June Ethiopia claims to have killed more than 110 rebels allegedly sent by Eritrea to destabilise the country, a claim denied by Eritrea.
There are meanwhile fears the feuding neighbours may be using Somalia as a proxy battleground.
As the dispute drags on, there are regular attacks and incidents in border regions. One of the worst is in June 2016 when fighting reportedly involving heavy artillery erupts, causing “significant” casualties although no death toll is immediately released.
© Agence France-Presse