Oil created the Anglo-Persian Oil Company (APOC) as a subsidiary and also sold shares to the public. Volume production of Persian oil products eventually started in 1913 from a refinery built at Abadan, for its first 50 years the largest oil refinery in the world (see Abadan Refinery). In 1913, shortly before World War I, APOC managers negotiated with a new customer, Winston Churchill, who was then First Lord of the Admiralty. Churchill, as a part of a three-year expansion program, sought to modernise Britain's Royal Navy by abandoning the use of coal-fired steamships and adopting oil as fuel for its ships instead. Although Britain had large reserves of coal, oil had the advantage of greater energy density, allowing a longer steaming range for a ship for the same bunker capacity. Furthermore, Churchill wanted to free Britain from its reliance on the Standard Oil and Royal Dutch Shell oil companies. In exchange for secure oil supplies for its ships, the British government injected new capital into the company and, in doing so, acquired a controlling interest in APOC. The contract that was set up between the British Government and APOC was to hold for 20 years. The British government also became a de facto hidden power behind the oil company. APOC took a 50% share in a new Turkish Petroleum Company (TPC) organised in 1912 by Calouste Gulbenkian to explore and develop oil resources in the Ottoman Empire. After a hiatus caused by World War I, it reformed and struck an immense gusher at Kirkuk, Iraq in 1927, renaming itself the Iraq Petroleum Company. In 1920, the APOC also acquired a northern oil concession that had been formally granted in 1916 to a former Russian subject, the Georgian Akaki Khoshtaria. To manage this new acquisition, the APOC formed a new subsidiary, the North Persia Oil Company, but the Persian refused to accept the new company, giving rise to a lingering dispute over the northern Persian oil. In 1923, a large quantity of oil was found at Naftkhana (now Khanaqin in Diyala Province), which was considered a "transferred territory" along the Persia-Iraq border. The Khanaqin Oil Company was registered in London as an APOC subsidiary. During this period, Persian popular opposition to the D'Arcy oil concession and royalty terms whereby Persia only received 16% of net profits was widespread. Since industrial development and planning, as well as other fundamental reforms were