Imports of copper and products by China, the world's largest consumer, unexpectedly climbed for the first time in three months.

Purchases increased to 399,052 metric tons in September, China's Customs said yesterday. That's 23 percent more than August, according to data compiled by Bloomberg.

Copper, used in pipes and power cables, has doubled in London this year as China's stimulus spending and State stockpiling boosted imports to a record, and the world recovered from its worst recession since World War II, increasing demand for raw materials.