UNITED NATIONS, Sept. 18 (Xinhua) -- UN Secretary-General Ban Ki-moon on Thursday appointed the former leader of Botswana and the immediate outgoing president of the UN General Assembly to be the UN's new special envoys on climate change.

    Festus Mogae, who was president of Botswana from 1998 until earlier this year, has extensive experience in economics and development planning, having also served as his country's finance minister and in the International Monetary Fund and the World Bank.

    As president of the General Assembly's 62nd session, which ended on Monday, Srgjan Kerim chaired three thematic debates on climate change, and also served as the foreign minister of the former Yugoslav Republic of Macedonia.

    They join two other special envoys appointed last May: Gro Harlem Brundtland, former Norwegian prime minister, and Ricardo Lagos Escobar, who used to serve as president of Chile.

    All Envoys will "support the secretary-general in his consultations with heads of states and of governments, as well as other key stakeholders," UN spokesperson Marie Okabe told reporters in New York.

    They will also push for progress in negotiations of the UN Framework Convention on Climate Change (UNFCCC), with the next round of talks slated to take place in Poznan, Poland, in December.

    The secretary-general also hopes the envoys will be able to promote positive steps towards reaching an "ambitious, comprehensive, inclusive and ratifiable" pact to succeed the Kyoto Protocol, whose first commitment period ends in 2012, Okabe said.