BEIJING, May 21 (Xinhua) -- China on Thursday called for the developed nations to reduce greenhouse gas emissions by 40 percent by 2020.

    "As a medium-range target for 2020, developed nations should collectively cut their greenhouse gas emissions by 40 percent from1990," Foreign Ministry spokesman Ma Zhaoxu told a regular briefing.

    Ma had been asked to convey China's position on the UN climate change conference in Copenhagen in December.

    Ma said China had recently issued a position paper, "Implementing the Bali Roadmap -- China's position on the Copenhagen Conference," which was available at www.sdpc.gov.cn., the website of the National Development and Reform Commission, the country's top economic planning body.

    Ma said the paper illustrated China's proposals on implementing the Bali Roadmap and the country's will to work for a positive outcome from the Copenhagen Conference, which will attempt to formulate a post-Kyoto deal on climate change.

    "The paper says the objective of the conference is to fully, effectively and continuously implement the UN Framework Convention on Climate Change and the Kyoto Protocol," Ma said.

    Ma said the paper stressed that the Copenhagen conference should adhere to the principles of "common but differentiated responsibilities" and sustainable development, and take measures to alleviate, adapt to the climate change and provide technology and financial support to countries in need.

    "China will, as always, firmly follow the path of sustainable development and make unremitting efforts to deal with the global climate change," Ma said.