ADDIS ABABA (Reuters) - Eritrea condemned a grenade attack at a rally in Addis Ababa attended by Ethiopian Prime Minister Abiy Ahmed, Eritrea’s ambassador to Japan wrote on Twitter.

“#Eritrea strongly condemns the attempt to incite violence, in today’s AA demonstration for peace, 1st of its kind in history of #Ethiopia.” Ambassador Estifanos Afeworki said on Twitter.

Ethiopia and Eritrea have long been at loggerheads over a border dispute. But Abiy stunned Ethiopians this month by saying he was ready to fully implement a peace deal with Eritrea that was signed in 2000 after a two-year war and which Addis Ababa had previously refused to implement without further talks.