A ferocious war between Ethiopia and Eritrea exploded again yesterday with a new round of heavy fighting along their disputed border.
The fighting, which is diverting vital resources away from the two countries' fight against drought, brought a hint of possible United Nations sanctions and a warning from the European Union that it posed a threat to continued EU food aid.
Ending a year's lull in the conflict and ignoring international calls for restraint, the rival armies traded artillery fire and deployed fighter jets to attack each other's positions.
Eritrea accused its enemy to the south of launching an offensive with "human wave assaults".
An estimated 600,000 soldiers are stationed along the border and tens of thousands were killed in two previous rounds of first World War-style fighting, with troops sent out from trenches to face massive artillery fire.
Eritrea, a former Ethiopian province granted independence in 1993, said Ethiopian artillery units began heavy shelling around midnight on Thursday in the biggest offensive since March last year.
Ethiopia said there was heavy fighting on the ground and in the air on all three war fronts - in the area of Badme on the western end of the border, near the town of Zalambessa in the centre and in Burre in the east.
A senior official privately admitted it was Ethiopia that had launched the attack to push Eritrean troops out of its territory, seized when the war first erupted in May 1998. "The aggressor must be punished," he said.
The fighting came just two days after a delegation of seven UN Security Council ambassadors abandoned the latest attempt to mediate a peaceful solution. The team shuttled back and forth between Ethiopia and Eritrea for two days trying to persuade both sides to reopen negotiations and, at the very least, maintain an unofficial ceasefire that had held fairly well for over a year.
"The differences between the two sides are real but they are small and can be resolved by diplomatic means," Mr Richard Holbrooke, the US ambassador to the UN, said. "The alternative is a senseless war which will kill tens of thousands of people, and hundreds of thousands will die of famine because of the diversion of resources to the war effort."
The current leaders of Ethiopia and Eritrea were once allies in their separate guerrilla wars against the former Ethiopian dictator, Mengistu Haile Mariam. Tensions later emerged over economic policy and rival claims along the border.
These exploded into war in May 1998. Eritrea seized large sectors of territory in the first round but Ethiopia won back control of Badme last year.