China has pledged to maintain the country's low birth rate so as to limit its population to 1.39 billion by 2015.

"From 2011 to 2015, the country's working-age population will peak, while the aging population will grow at an unprecedented rate. And the urban population will remain greater than that in rural areas," said a guideline on the country's population development in 2011-15.

According to the document, issued on April 10 by the State Council, China's cabinet, the overall population growth rate will be kept below 0.72 percent per annum.