Developing nations must play a major role in reducing greenhouse gas emissions, a senior U.S. official reiterated Oct. 16 in Tokyo, indicating that this will be a focal point in negotiations during a key U.N. conference on global warming to be held in Kyoto in December."The position that we have taken is that it is absolutely imperative that the developing countries also assume responsibilities," said Timothy Wirth, U.S. undersecretary of state for global affairs.Toward this end, the U.S. has proposed that new categories with their own responsibilities be created for rich developing nations, like South Korea, and that very large developing countries such as China, India and Indonesia gradually shoulder increased responsibility, Wirth told a gathering at the Tokyo American Center. The conference of the parties to the U.N. Framework Convention on Climate Change will be held in Kyoto from Dec. 1 to 10.Wirth said Washington will unveil its own proposal to cut greenhouse gas emissions "in a few days." The U.S. proposal will probably incorporate a complex formula, similar to the one proposed earlier by Japan, he added.Wirth lauded Japan's proposal to cut emissions by 5 percent from 1990 levels by 2012, and criticized the European Union proposal that calls for a 15 percent reduction by 2010. Wirth characterized the Japanese proposal as more clear and realistic, and expressed skepticism at the EU's ambitious plan."We have a lot of questions to the Europeans about how they are going to make this commitment. It is not at all clear to us that this is feasible and realistic. The United States believes that the proposal made by the Japanese is in fact reachable and is feasible and realistic," he said.In addition, the U.S. proposal will probably include a policy of emissions trading, a system rewarding nations that reduce emissions beyond the goal by permitting them to sell the emissions within that allowed margin to countries that fall behind. Emissions trading would allow for development of financial instruments that use the market to help meet the reduction goal, Wirth said, adding that the United States successfully instituted a similar system to reduce air pollution."To bring all of these disparate ideas together into one solution is the most complicated negotiation that the world has ever undertaken," Wirth said. Reducing emissions is a long-term issue posing huge technological problems of which the Kyoto meeting is only the beginning, so it is important to agree to an achievable objective, Wirth said.