UN peacekeepers on Thursday began pulling out of the Eritrean side of the tense border region with Ethiopia, saying the Asmara government’s freeze on vital fuel supplies made the continuation of the mission impossible.

The pullout came despite a decision of the Security Council last month to extend the mandate of the 1,700 force by a further six months. Eritrea has refused to lift its fuel ban as part of a dispute with Ethiopia over implementation of a border arbitration decision that followed their 1998-2000 war.