The Xinhua news agency said the 1,000-kilometer pipeline is designed to carry 20 million tons of oil annually from Kazakhstan to China.
The report said the Altaw Pass, where the final pipeline link was welded on 13 November, is expected to become a hub for railway, road, and pipeline networks in the remote border region in China's northwest.
The pipeline was built by the state-owned China National Petroleum Corporation and the Kazakhstan National Petroleum and Natural Gas Company.
The same Chinese company recently completed its acquisition of the Canada-based PetroKazakhstan, whose energy assets are all in Kazakhstan.
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