dollar string of deals to develop oil and gas fields and buy fuel supplies from countries as far-flung as Sudan, Venezuela and Australia. During a visit to Kazakhstan in early July, Chinese President Hu Jintao agreed to boost strategic ties with the energy-rich Central Asian nation neighboring China. Hu and Kazakh President Nursultan Nazarbayev signed a strategic partnership declaration after talks in the capital, Astana. CNPC already owns oil exploration and production licenses in Kazakhstan and is a partner with Kazak state-owned oil company KazMunaiGaz in the construction of a 988-kilometer (620-mile) pipeline to carry oil to China. CNPC is the parent company of PetroChina Co. Ltd., China's biggest oil producer. PetroChina's shares are traded on stock exchanges in Hong Kong and New York. PetroKazakhstan is based in Calgary, Canada but all of its operations are in Kazakhstan. Kazakhstan currently exports about 800,000 barrels of oil a day and is expected to become one of world's top oil suppliers within two decades.