The White House on Tuesday denied it was planning a U-turn on its climate change policy by embracing a system of formal caps on greenhouse emissions, despite rising pressure from European governments to change its stance.

Although energy security will be a key theme in President George W. Bush’s State of the Union address next week, the White House issued an unusually public rebuttal of rumours about its climate change policy. Tony Snow, White House spokesman, said: “I want to walk you back from the whole carbon cap story...The carbon cap stuff is not accurate. It’s wrong.”