International Climate Campaigner Tom Picken said:"Obama's pledge to go to Copenhagen is a welcome and significant development - but he must adopt a 'yes we can' attitude in the UN climate talks if he is to earn his Nobel prize. "The US is the world's biggest per capita polluter. It has a moral responsibility to take the lead in securing a strong and fair agreement. "US engagement at the UN climate talks to date has been inadequate and often damaging. "Obama must show the US is willing to slash its emissions without carbon offsets and agree a comprehensive finance and technology package to support developing countries to grow cleanly and deal with the impacts of climate change. "The world is stumbling towards a climate catastrophe - bold international leadership is desperately needed." Notes to Editor 1. Friends of the Earth believes the environment is for everyone. We want a healthy planet and a good quality of life for all those who live on it. We inspire people to act together for a thriving environment.