President Barack Obama urged the world to take immediate action to combat global warming during a special U.N. summit, but did not introduce any new proposals to revive stalled discussions on a UN climate agreement. Chinese President Hu Jintau also committed to reducing the carbon intensity of China's economic growth in his address following Obama's. Obama emphasized the urgency of the situation, warning that failure to address the issue swiftly and decisively could lead to irreversible consequences for future generations. He stressed that time was running out to reverse the effects of global warming. Activists were optimistic that the United States and China would provide a boost before the climate change summit in Copenhagen, where 190 nations will convene to finalize an agreement. U.N. Secretary-General Ban Ki-moon, who organized the meeting, expressed concern over the slow progress in negotiations. Ban stressed the importance of reaching a comprehensive agreement in Copenhagen, warning that failure to do so would be morally unacceptable, economically foolish, and politically unwise. He emphasized the interconnectedness of global issues and the need for collective action. Discussions leading up to the December 7-18 meeting have caused tension between developed and developing countries regarding how to allocate emissions reductions. Developing nations are urging developed countries to provide significant financial assistance to help them address the impacts of climate change. European Commission President Jose Manuel Barroso expressed concern that the talks are close to a standstill and could collapse in a contentious manner. Obama and Hu, scheduled to meet separately after the summit, could potentially help resolve the deadlock. If China were to take a proactive stance in reducing emissions, it could ease criticism from U.S. lawmakers hesitant to commit to emission cuts without assurance of Chinese cooperation. Obama's efforts to decrease U.S. emissions through legislation have been less prominent than his focus on healthcare reform. However, he stated in a speech that the United States has made more progress in the past eight months in reducing carbon pollution than ever before.