China's state reserves manager signed agreements today with six smelters to buy 300,000 metric tons of aluminum at 15,137 yuan ($2,434) a ton in a bid to bolster local prices.

The State Bureau of Material Reserve will pay about 4 percent more than the spot price for the metal to be delivered in April and May, data provider SMM Information & Technology Co. said on its website today. That compares with a spot price of 14,550 yuan on Shanghai's Changjiang Nonferrous Metal Market.

"The stockpiling plan could help tighten the market in April and May," Huang Fulong, an analyst at Citic Securities Futures Co., said by phone from Shenzhen. "The agreed price was slightly lower than market expected."

The sellers include Aluminum Corp. of China Ltd., better known as Chalco, China Power Investment Corp., Yunnan Aluminum Co. and Henan Shenhuo Coal & Power Co., according to SMM. The reserves manager last bought 100,000 tons in November.

Aluminum for delivery in three months on the London Metal Exchange traded at $1,983 at 11:52 a.m. in Shanghai. The most- actively traded contract on the Shanghai Futures Exchange was at 14,855 yuan a ton.