Shortly after, on 22 September 2009, he hosted a Summit on Climate Change to promote leader-level engagement in the final push towards a global agreement in Copenhagen. The Summit, presided over by Danish Prime Minister Lars Lokke Rasmussen, attracted what was then the largest-ever number of Heads of State and Government to gather and focus specifically on climate change. While negotiations made little progress throughout the fall, the unprecedented engagement of global leaders, the private sector and civil society on the issue, the unequivocal urgency of the issue according to science, and the election of Barack Obama as United States President led many to think that an ambitious outcome to COP 15 was assured. While this was beginning to change, world leaders still lacked confidence about what or how their country could contribute to climate change mitigation.81 In addition, deep mistrust prevailed between developed and developing countries.