"Mining group BHP Billiton climbed to the top of the FTSE 100 leaderboard, pushed up by rumours that a major stake could be taken in the company. Dealers speculated that the stake would be used to try to block BHP's hostile takeover of Rio Tinto, as it plans to create one of the world's biggest companies."
http://www.telegraph.co.uk/money/main.jhtml?xml=/money/2008/04/09/cxmktrep109.xml