"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 late Monday, citing local authorities in the disputed area, which is claimed by Tigray and neighbouring Amhara.

"The humanitarian situation is dire, with thousands of women and children in need of broad humanitarian support to survive," it added.

Amhara forces occupied Raya Alamata in southern Tigray during a two-year war between Ethiopia's government and regional Tigrayan authorities.

Under a peace deal between Prime Minister Abiy Ahmed's government and Tigrayan authorities, Amhara forces -- which backed federal troops during the conflict -- were due to withdraw from Raya Alamata after the agreement was signed in Pretoria in November 2022.

Neither the federal government nor Tigrayan authorities responded to AFP requests for information. It is impossible to verify the situation on the ground independently as media access to northern Ethiopia is heavily restricted.

Reports of the fighting have sparked alarm among the international community, with the embassies of several nations including the United States, Japan, Britain, and France on Saturday calling for dialogue and urging the "de-escalation and protection of civilians".

During the war, Amhara forces occupied and remained in control of western Tigray, a disputed region claimed by both regions.

Amhara, Ethiopia's second most populous region, has been wracked by clashes since April 2023, when the federal government's decision to dismantle regional forces across the country triggered clashes.

Amhara nationalists, who felt betrayed by the Tigray peace deal, said the move would weaken their region.