A meeting in Washington of global political leaders has reached a new agreement on tackling climate change.
Delegates agreed that developing countries will have to face targets for cutting greenhouse gas emissions as well as rich countries.
The informal meeting also agreed that a global market should be formed to cap and trade carbon dioxide emissions.
The non-binding declaration is seen as vital in influencing a replacement for the Kyoto Protocol, correspondents say.
The forum's closing statement said man-made climate change was now "beyond doubt".
In a related story:
EU energy ministers have agreed to increase the share of biofuels used in transport to 10% by 2020.
But at a meeting in Brussels they were unable to decide whether a target of getting 20% of energy from renewable sources by 2020 should be binding.