The leaders of China and Kazakhstan have agreed to finance and build a network of pipelines to supply the world's fastest-growing major economy with oil and gas from the Caspian Sea region.

"The Caspian will be linked to western China," Kazakh President Nursultan Nazarbayev told reporters in the capital Astana on Saturday after meeting with Chinese President Hu Jintao. "These are major projects, and today we reached agreement on these issues."

Kazakhstan's Atasu-Alashankou oil route will be extended and a gas link from Turkmenistan to China through Kazakhstan will be built, Bloomberg News quoted Nazarbayev as saying. The gas link will bypass Afghanistan, Tajikistan and Kyrgyzstan, landlocked countries between Turkmenistan's Caspian shore and China.

Kazakhstan and Turk-menistan are the biggest energy suppliers in the former Soviet Union after Russia. The Caspian region they share with Azerbaijan, Iran and Russia holds about four percent of the world's proven oil and gas reserves. The gas pipeline will be able to move 30 billion cubic meters of fuel a year and cost as much as US$4 billion to build, Energy Minister Baktykozha Izmukhambetov said in November.

The 750-kilometer extension of the Atasu-Alashankou oil pipeline will connect China with two oil fields, Kenkiyak and Kumkol, owned and operated by Kazakh units of state-run China National Petroleum Corp. The pipeline will have a capacity of 400,000 barrels a day, or about five percent of China's consumption.

China National Petroleum Corp, the biggest Chinese oil producer, said it will expand oil and gas cooperation with Kazakhstan after spending more than US$6.5 billion so far on oil exploration, refining and pipelines in the country.