Rival Libyan factions have reached an agreement in principle to have one oil organisation for the strife-torn north African OPEC member, the foreign minister of the new U.N.-backed unity government said on Tuesday. "These institutions can only be managed centrally. That's why it was agreed that both institutions from east and west be united, so that there is only one oil company, one investment company and one central bank," Foreign Minister Mohammed Siyala told reporters in Vienna."The first steps to achieve this are being taken now, there is an agreement on the basic points and principles and now we're waiting for the implementation."The West is counting on the unity government to tackle Islamic State in Libya and stop new flows of migrants heading across the Mediterranean, though the new leaders are still not in control of the capital city, Tripoli. ..