Refined copper imports by China, the world's largest consumer, climbed for the first time in three months in September as increasing demand outweighed the higher costs of overseas material.

Shipments increased to 282,828 metric tons in September, the Beijing-based customs office said today. That's 29 percent more than August, according to data compiled by Bloomberg.

Copper, used in pipes and power cables, has more than doubled in London this year as China's 4 trillion yuan ($586 billion) 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.

"Shanghai copper prices will continue to stay weak compared with London because of the gains in imports as well as in domestic production," Li Ye, an analyst at Minmetals Starfutures Co. said from Shenzhen today. "That doesn't seem to be stopping China from buying though."

China's copper output gained 8 percent to 395,000 tons in September, from a month ago, the statistics bureau said last week. That's a record, Li said.

Exports of refined copper were 10,705 tons, 70 percent higher than a month ago and the highest this year, customs data showed.

"The monthly figure was quite a lot and was a result of inbound shipments remaining money-losing," Zhao Kai, an analyst at Jinrui Futures Co. said today.

Copper for delivery in three months on the London Metal Exchange gained 0.5 percent to $6,680 a ton at 9:49 a.m. Shanghai time. The metal for January delivery on the Shanghai Futures Exchange added 0.4 percent to 51,550 yuan ($7,550) a ton at the same time.