China's President Hu Jintao has vowed to reduce carbon dioxide emissions produced by his country, one of the largest polluters in the world.

In a speech to world leaders at the U.N. climate change summit in New York on Tuesday, Mr. Hu said China plans to get 15 percent of its energy from renewable sources by the year 2020. 

He also said China will cut greenhouse gases by a "notable margin" by 2020 from 2005 levels.  He did not set a figure for the cuts, saying they will be made based on China's economic output.

Speaking at the summit, Japan's new Prime Minister Yukio Hatoyama told world leaders his nation plans to reduce greenhouse gas emissions by 25 percent from 1990 levels by 2020.

Prime Minister Hatoyama and President Hu also called for financial support from developed countries - to help developing nations achieve climate change goals and sustainable development.

Some information for this report was provided by AFP and AP.