The United States has expressed deep concern about increasing ethnic and political polarisation across Ethiopia.

Washington said it would work with allies to secure a ceasefire in the northern region of Tigray, where conflict erupted last November.

“The atrocities being perpetrated in Tigray and the scale of the humanitarian emergency are unacceptable,” the US state department said.

It promised to hold accountable those who abused human rights.

The US special envoy, Jeffrey Feltman, on Thursday returned from a trip to the Horn of Africa.

He said he told Eritrean President Isaias Afwerki that he must immediately withdraw his troops from Tigray.

Ethiopian and Eritrean forces have been accused of serious abuses in Tigray.