Naturally the existence of this secret treaty was an embarrassment to the British officials in Egypt in their negotiations with the Arabs. However, an Arab rebellion was too valuable an asset to be lost, and the British negotiators finally evolved a formula which satisfied the Arab leaders. On October 25, 1915, the Shereef of Mecca's representative at Cairo was given a document by the Governor-General of Egypt, Sir Henry McMahon, in which Great Britain undertook, conditional upon an Arab revolt, to recognize the independence of the Arabs of the Ottoman Empire except in southern Mesopotamia, where British interests required special measures of administrative control, and also except areas where Great Britain was "not free to act without detriment to the interests of France." This last clause was of course a "joker." However, it achieved its purpose. The Arabs, knowing nothing about the secret treaty, supposed it referred merely to the restricted district of the Lebanon. They went home jubilant, to prepare the revolt which broke out next year. The revolt began in November, 1916. It might not have begun at all had the Arabs known what had happened the preceding May. In that month England and France signed another secret treaty, the celebrated Sykes-Picot Agreement. This agreement definitely partitioned Turkey's Arab provinces along the lines suggested in the initial secret treaty of the year before. By the Sykes-Picot Agreement most of Mesopotamia was to be definitely British, while the Syrian coast from Tyre to Alexandretta was to be definitely French, together with extensive Armenian and Asia Minor regions to the northward. Palestine was to be "international," albeit its chief seaport, Haifa, was to be British, and the implication was that Palestine fell within the English sphere. As to the great hinterland lying between Mesopotamia and the Syrian coast, it was to be "independent Arab under two spheres of influence," British and French; the French sphere embracing all the rest of Syria from Aleppo to Damascus, the English sphere embracing all the rest of Mesopotamia--the region about Mosul. In other words, the independence promised the Arabs by Sir Henry McMahon had vanished into thin air.