Russia's Rusal board chairman steps down in line with U.S. instructions

MOSCOW (Reuters) - Russian aluminium giant Rusal said on Wednesday that Matthias Warnig, chairman of its board of directors, had resigned as part of a restructuring process the company agreed to implement so that the U.S. Treasury can remove it from the sanctions list.The U.S. Treasury said last week it would remove sanctions against Rusal, its parent En+ and power firm EuroSibEnergo if they restructured to reduce the stake of businessman Oleg Deripaska, who is under U.S. sanctions. Warnig's..