The United Nations Framework Convention on Climate Change (UNFCCC) has received submissions of national pledges to cut and limit greenhouse gases by 2020 from 55 countries. They include the US, all EU countries and China, as well as major emerging economies such as Brazil, Indonesia and India. The 55 nations between them emit 78% of the world's greenhouse gases. But, significantly, the group includes only Brazil from South America, and just six out of 55 African countries. In all, 137 countries have not made pledges. "This represents an important invigoration of the UN climate change talks under the two tracks of Long-term Cooperative Action under the Convention and the Kyoto Protocol," said Yvo de Boer, Executive Secretary of the UNFCCC. "The commitment to confront climate change at the highest level is beyond doubt. These pledges have been formally communicated to the UNFCCC. Greater ambition is required to meet the scale of the challenge. But I see these pledges as clear signals of willingness to move negotiations towards a successful conclusion," he said.