In its annual Trade and Development Report, the agency said China has played "a vital role" in helping the economic growth of other developing countries.

"Since the beginning of the 1990s, China's domestic demand and its imports have grown very strongly indeed, and the country has played a vital role in spreading and sustaining growth momentum throughout the developing world," the report said.

Such a process should not be derailed, and therefore, renminbi revaluation should continue gradually rather than abruptly, taking due account of regional implications, it noted.

The UNCTAD also praised China's sharp economic growth in recent years, indicating China's characteristic growth, which highlights a government role in the market, could be a model for poor countries.

The report said governments of developing countries should " take a pro-active stance in macroeconomic and industrial policies to accelerate private investment and technological upgrading and to stimulate the creative forces of markets."

The hands-off policy and total reliance on market forces, as promoted by international financial organizations and lenders in the 1980s and 1990s, has proved to be a failure for many developing nations, it said.

According to the report, developing countries could post a high economic growth rate of 6.2 percent in 2006. While wealthy nations, including the United States, European Union and Japan, should achieve a growth rate of 2.7 percent this year.

The global average growth should be 3.6 percent this year, the same with last.

Excluding China's booming economy, the fastest growth rates this year should be posted seven percent in Asia and 5.9 percent in Africa, where growth has accelerated consistently since 2002.

The report highlighted the role of China and India, the two most populous countries in the world, in boosting the global economic growth.