China has become one of the seven most unequal countries in Asia, with the level being close to that in Latin American economies, according to the bank's report, 'Key Indicators 2007 Inequality in Asia' launched in Beijing.

"The poor have benefited less from growth than the rich," said the ADB's chief economist Ifzal Ali, warning that sharp inequality may lead to a decline in social cohesion.

Juzhong Zhuang, assistant chief economist of the bank, said that corruption, made possible by government officials' privileged access to resources and information, was one of the key reasons for widening inequality in China.

"The government has quite a big role in allocating resources (and) some individuals and companies are manipulators of certain resources or sectors, or they have special contacts or exclusive information," he said.

Hoping to curb rising social unrest, China has made narrowing the wealth gap a key target in its development plan running to 2010, with policies such as subsidies and low-interest loans being directed to farmers and the poor.

But Ali said that huge differences remain in terms of access to public services such as health care and education.

Efforts should be taken to prevent legal, political and economic institutions from being captured by the few so that social tensions could be reduced, he said.

"If we can ensure an even playing field and the starting gate is the same for all, (the) possibility of upward mobility for people will take a lot off the frustration that is now ... associated with the growth process," said Ali.

"This upward mobility, the prospects for it, would in my view alleviate some of the acute problems of social tensions that we now witness in different parts of Asia."