President Barack Obama said on 30 November the Paris climate conference was a turning point to address the growing threat of climate change and that the US, as the world's second biggest emitter of greenhouse gases, recognised its role in creating the problem of global warming and embraced its responsibility to help fix it.
Obama said: "Nearly 200 nations have assembled here this week. A declaration that for all the challenges we face, the growing threat of climate change could define the contours of this century more dramatically than any other. And what should give us hope? That this is a turning point. That this is the moment we finally determine we would save our planet. It's the fact that our nations share a sense of urgency about this challenge and a growing realisation that it's within our power to do something about it.
"As the leader of the world's largest economy and the second largest emitter... the United States of America not only recognises our role in creating this problem, we embrace our responsibility to do something about it," Obama added, addressing nearly 150 world leaders at the start of two weeks of UN talks in Paris.
The US president called on all leaders gathered to secure an agreement paving the way for regularly updated targets that would help "lift people from poverty without condemning the next generation to a planet that's beyond its capacity to repair". The UN summit will see two weeks of bargaining in a bid to reach a deal aimed at steering the global economy away from its dependence on fossil fuels.
The US and China – the world's biggest emitter of greenhouse gases – have in the past resisted signing up to a global deal to address climate change. This time, they have pledged to work together, although both nations have issues with the UN process and are expected to struggle to accept a legally binding global pact.