SHANGHAI, Jul. 4 (SMM) - Spot aluminium stockpiles fell for the 13th consecutive week in China as some producers delivered their output to State Reserve Bureau (SRB), according to a survey by Shanghai Metals Market.

Stockpiles of the lightweight metal on a spot basis in China’s four major trading regions – Shanghai, Wuxi, Nanhai and Hangzhou -- dropped to 875,000 tons this week. They were down 41,000 tons from a week ago, and compared to this year’s high of 1.3 million tons in the week of April 8.

After China's SRB issued tenders to buy 300,000 tons of primary aluminium in March, producers that won the tenders did not complete making deliveries until mid June, reducing free market supplies.

At the same time, many producers increased processing rate of their primary output while some producers in China’s northwest regions had difficulty transporting their output here.