BEIJING - China on Tuesday unveiled guidelines to reform its income distribution mechanisms amid growing public concern over a widening wealth gap.

The reform will focus on increasing residents' income, narrowing the income distribution disparity and regulating the distribution order, said a statement from the State Council, or China's cabinet, which declared approval and transfer of the guidelines.

The government will work to double the average real income of urban and rural residents by 2020 from the 2010 level and let the poor enjoy faster income growth, according to the guidelines.

The middle-income group will be expanded and the number of those living under the poverty line will be sharply reduced, while excessively high and hidden income will be adjusted and regulated, they said.

The reform also targets raising the proportion of residents' income in the overall national income and spending more government funds on social security and employment.

"Both efficiency and fairness should be considered in the initial distribution and redistribution processes," the State Council said.

It hailed the reform as significant to the country's bid to transform the pattern of its economic development into one that is more consumption-driven.

Fairer income distribution is a fundamental move to safeguard equity and justice as well as social stability and harmony, it said.

However, "deepening the income distribution reform is a systematic project that is arduous and complicated and concerns the reallocation of various interests," said the cabinet. "There is no way to accomplish it overnight."

A task force was set up in October 2010 to study income distribution reforms, involving experts from the National Development and Reform Commission, the Ministry of Finance and the Ministry of Human Resources and Social Security.

The State Council urged local governments and various departments to map out supporting schemes and detailed rules for implementation of the guidelines.

As China's economy catapulted to the world's No. 2 position, the country also saw its income gap yawning.

The Gini coefficient, a rich-poor index, reached 0.474 in China in 2012, higher than the warning level of 0.4 set by the United Nations, said the National Bureau of Statistics, with the news marking the first time China announced an official broad-based Gini coefficient since 2000.

Both central authorities and economists have urged accelerated reforms of the income distribution system to bridge the wealth gap for more sustainable development.

China will work to boost national incomes, deepen reforms on the income distribution system and enable people to share the country's development achievements, according to a keynote report delivered at the 18th National Congress of the Communist Party of China.