Ethiopian government forces have made major advances in their fight against Tigrayan dissidents after a 13-month conflict that’s triggered humanitarian and economic crises.

Tigrayan leader Debretsion Gebremichael this week ordered a strategic retreat by his troops and urged the United Nations Security Council to oversee an end to the civil war. The move, which comes after the national army recaptured several key towns in northern regions bordering on Tigray, raised hopes that an end to hostilities may be in sight, though the government has continued bombing rebel positions.

"I have ordered those units of the Tigray army that are outside the borders of Tigray to withdraw to Tigray with immediate effect,” Debretsion, who heads the Tigrayan Peoples Liberation Front (TPLF) which ruled the region, said in a Dec. 19 letter to U.N. Secretary-General Antonio Guterres. "We trust that our bold act will be a decisive opening for peace.”