UNITED NATIONS - UN Secretary-General Ban Ki-moon renewed his call on all sides in Libya to commit to a political process, lamenting the lack of progress in efforts to resolve the ongoing conflict. Libya has been engulfed by fighting since the opponents of Libyan leader Gaddafi emerged in February following similar protests in Tunisia, Egypt and other countries across North Africa and the Middle East. In a telephone call on Wednesday, Ban told PM Baghdadi al-Mahmoudi of Libya that he was very troubled that there had been an absolute lack of progress in the efforts to find a politically negotiated solution to the crisis, despite the efforts of his Special Envoy, Abdel-Elah Al-Khatib. He said all sides must commit to a political process, and urged the Prime Minister to respond constructively to the Special Envoys ideas, according to a read out provided by Bans spokesperson. UN officials have repeatedly stated that a ceasefire tied to transitional arrangements which address the aspirations of the Libyan people is the only sustainable political solution to the crisis. However, the parties remain divided on how to reach a political solution to the conflict, which has caused an estimated 630,000 people to flee Libya since February and displaced another 200,000 within the country. AFP adds: A Libyan cargo plane seized by authorities in the UAE was handed over to rebel forces in their eastern bastion of Benghazi, a rebel official told AFP on Thursday. The four-engine Ilyushin-76TD aircraft arrived in Benghazi on Wednesday, said Colonel Abdel Nasser Bousnina.