On a leafy street in Almaty, a few hundred miles from Kazakhstan’s border with China, the elegant mansion of China National Petroleum Corporation is kept under close guard. Behind its closed shutters, Chinese oilmen have plotted a strategy to win a huge portfolio of Kazakh energy assets to feed their country’s need for oil.

China began discreetly buying Kazakh oilfields 10 years ago and now has more energy projects on the go in the central Asian nation than any other country. While the west’s biggest oil groups agonise over the risks of undertaking expensive infrastructure developments in obscure locations, Beijing has boldly built a 3,000km pipeline to lock Kazakhstan’s oilfields into its orbit.