More than 50,000 people have been displaced by clashes in a disputed area of northern Ethiopia, the United Nations said, as the international community expressed concern over the violence involving fighters from rival regions.

"The number of people displaced by the armed clashes in Alamata Town, and Raya Alamata, Zata and Ofla ... since 13/14 April has reached more than 50,000," the UN said on Monday, citing local authorities in the disputed area, which is claimed by Tigray and neighboring Amhara.