President Obama unveils new climate action plan
25 June 2013 Last updated at 20:05 BST
President Obama has announced a new climate action plan to limit the emission of greenhouse gases in the United States.
In a speech at Georgetown University, Mr Obama launched the first-ever federal regulations on carbon dioxide emitted by US power plants.
Mr Obama vowed to put an end to the "limitless dumping of carbon pollution from power plants".
Congress has previously blocked Mr Obama's attempts to reduce the emission of greenhouse gases.