The Chinese leader endorsed the "Copenhagen Accord" in letters on January 29 to the United Nations Secretary-General Ban Ki-moon and Danish Lars Lokke Rasmussen, whose country hosted the rancorous summit that produced the controversial, last-minute document on fighting global warming, the official Chinese Xinhua news agency reported on Monday.

Since then, China and over other 50 nations have outlined their plans for reducing greenhouse gases and addressing climate change under a January 31 deadline, aiming to set in motion negotiations seeking a full pact in Mexico late in 2010.

In its submission, China repeated what it calls a voluntary domestic goal to cut the amount of the main greenhouse gas, carbon dioxide, produced for every unit of economic output by 40 to 45 percent by 2020, compared to levels in 2005.

This "carbon intensity" goal would let China's greenhouse gas emissions keep rising, but more slowly than economic growth.