The US has rejoined the global effort to develop a successor agreement to the Kyoto Protocol, which is set to expire in 2012. US diplomats participated in the first round of negotiations in Bonn in March-April 2009. Four more rounds are scheduled before the United Nations Climate Change Conference in Copenhagen this December, where the new agreement is to be finalized. On April 27, 2009, Secretary of State Hillary Clinton told international delegates to a preparatory meeting in Washington that "the United States is fully engaged and ready to lead and determined to make up for lost time both at home and abroad".