It cannot come from the Gulf states either because they finance ISIS and are interested in keeping the oil price low at a time when the world is awash with oil.
If one eliminates Western nations who say they wish to destroy ISIS and have no need to send tankers to pick up oil which they do not need from their sworn enemy, ISIS, one is left with Israel, the Lebanon, Syria itself and the countries of the Far East. One can rule all of these out because of lack of shipping capacity and the fact that the countries of the Far East get most of their oil from their own sources in Africa and the Gulf States directly.
President Erdogan‘s son and his cronies in the shipping business are the likely culprits based on the balance of probabilities and the sheer fact of Turkey’s geographical position, plus the fact that President Erdogan has imperial ambitions and has been providing logistical support to ISIS. President Erdogan’s assurances about resigning are, of course, worthless because by helping ISIS he is aiding our enemies and the enemy of NATO whilst still keeping his country as a NATO member.
Turkey has form going back 1000 years in terms of its imperial ambitions, duplicity and hostility towards Europe, Russia and China. Like Leopards, it has not changed its spots and need to be seen and dealt with as the double-dealing, untrustworthy entity it always was.