United Nations Secretary-General Antonio Guterres said on Thursday that he was gravely concerned by the rapidly deteriorating situation in northern Ethiopia, a day after the federal government and the TPLF accused each other of launching offensives, in what appears to be a return to full-scale conflict.

The Secretary-General called on all parties to exercise maximum restraint, immediately de-escalate tensions, protect civilians, ensure safe and unhindered access for humanitarian partners to reach those in need, and avoid actions that could lead to a broader and more devastating conflict.

Ethiopian Airlines said that flights to Mekelle and the cities of Shire and Axum had been halted “due to the current situation in Tigray region,” without giving further details.

Guterres also backed African Union efforts to ease tensions, including the involvement of former Nigerian President Olusegun Obasanjo, and urged the parties to return to good-faith talks under the Pretoria Agreement.