At the United Nations Climate Summit, U.S. President Barack Obama said that not only developed nations, but also developing nations, must act together to curb greenhouse gas emissions.

Chinese President Hu Jintao also pledged to cut carbon emissions, relative to economic output, by 2020.

Despite the talks, critics contend that world leaders had little to offer in the way of concrete proposals at the Sept. 22 United Nations Climate Summit.

Below, Jose Manuel Barroso, President of the European Commission, the executive body of the European Union, speaks about climate change.

Below, UK Foreign Secretary David Miliband talks about UK goals for the meeting.

The video below asks whether India can be the “deal maker” when it comes to climate change.