A congressional investigation has found that US Vice President Dick Cheney’s office backed efforts by ExxonMobil and other oil industry players to scupper support among several top Bush Administration officials for using the US’s Clean Air Act to limit greenhouse gas emissions.
http://www.upstreamonline.com/live/article159516.ece

It's interesting even the office of President's Chief of Staff initially supported the EPA's power to set greenhouse gas standards only to be over-rule by Cheney's office (again).

It shows who has the real power and influnce in this administration.