President of Aluminum Corp of China (Chinalco) Xiao Yaqing (C) speaks to members of the media after a news conference in London February 1, 2008. China teamed up with U.S. aluminium producer Alcoa to buy a $14 billion stake in Rio Tinto on Friday and said it may make a bid, threatening miner BHP Billiton's efforts to win Rio. REUTERS/Stephen Hird (BRITAIN)