In the Constantinople Agreement of 18 March 1915, following the start of naval operations in the run up to the Gallipoli campaign the Russian Foreign Minister, Sergey Sazonov, wrote to the French and UK ambassadors and staked a claim to Constantinople and the Dardanelles. In a series of diplomatic exchanges over five weeks, the UK and France both agreed, while putting forward their own claims, to an increased sphere of influence in Iran in the case of the UK and to an annexation of Syria (including Palestine) and Cilicia for France. The UK and French claims were both agreed, all sides also agreeing that the exact governance of the Holy Places was to be left for later settlement. Were it not for the Russian Revolutions of 1917, Constantinople and the Straits could have been given to Russia upon the Allied victory. This agreement and the Sykes–Picot Agreement were complementary, as France and Britain first had to satisfy Russia in order to finalize the partitioning of the Middle East.