PARIS: Yvo de Boer, head of the UN's climate change convention, will resign as of July 1, his office announced on Thursday. De Boer, executive secretary of the UN Framework Convention on Climate Change, will join the consultancy group KPMG as global advisor on climate and sustainability and work with a number of universities, the UNFCCC secretariat said. The announcement came nearly two months after the Copenhagen summit on climate change, seen even by its supporters as a disappointment and by its critics as a chaotic failure. The UNFCCC, an offshoot of the 1992 Rio summit, gathers 194 nations in the search for combatting the causes of man-made climate change and easing its effects. Its key achievement is the Kyoto Protocol, the only international treaty that requires curbs in heat-stoking greenhouse gases blamed for disrupting the climate system. In a statement, de Boer said it had been a "difficult decision" to step down. "I believe the time is ripe for me to take on a new challenge, working on climate and sustainability with the private sector and academia," he said. "Copenhagen did not provide us with a clear agreement in legal terms, but the political commitment and sense of direction toward a low-emissions world are overwhelming. "This calls for new partnerships with the business sector and I now have the chance to help make this happen." A Dutch national, de Boer was appointed the UNFCCC's executive secretary in September 2006. He had pinned hopes on a breakthrough in Copenhagen that would unlock a new treaty on climate change that would take effect after 2012, when the Kyoto Protocol's current pledges expire. Instead, after nearly two weeks of talks, the summit was only able to yield a general agreement on limiting warming to two degrees Celsius (3.6 degrees Fahrenheit). The accord did not spell out the means for achieving this goal, and the pledges made under it are only voluntary. The document did not gain approval at a plenary session of the UNFCCC, and it has so far failed to gain the official endorsement of major developing emitters which helped to craft it.