The Cuban and Chinese national flags fly next to each other at an oil rig of the Great Wall Drilling Company, a subsidiary of China National Petroleum Corp (CNPC), near Varadero, around 140 kilometres (86 miles) east of Havana, September 4, 2011. China has signed an agreement to play a major role in increasing Cuban oil production both onshore and offshore, although details were not disclosed. State-owned CNPC is said to be considering leasing exploration blocks in Cuban waters. China also committed to negotiations of contracts for a $6 billion expansion of Cuba's Cienfuegos refinery and a liquefied natural gas project. Picture taken September 4, 2011. REUTERS/Desmond Boylan (CUBA - Tags: ENERGY POLITICS BUSINESS)