Former prime minister Mahmud Abbas was appointed the new overall head of the Palestine Liberation Organisation (PLO) Thursday after the death of its long-time leader Yasser Arafat, official sources said. "Abu Mazen (Abbas) has been appointed head of the PLO," said a source in the Palestinian presidency's office. The widely-expected decision was confirmed at a meeting of the PLO's decision-making executive committee in the West Bank town of Ramallah.