Aluminum is "attractive at these levels" with 20 percent of China's production losing money, Goldman Sachs Group Inc said.

Up to 30 percent of aluminum output outside of China is "loss-making", Goldman Sachs said in a report.

"An expected pick-up in consumption would likely tighten the aluminum balance. This tightening, together with anticipated upside in oil prices, and upside risk surrounding potential Indonesian bauxite export quotas, leave us bullish from here."