Passengers line up and wait for a security check during morning rush hour at Tiantongyuan North Station in Beijing May 27, 2014. [Photo/Agencies]

Beijing plans to control the size of its population and to have no more than 23 million people by 2020, said a national legislator and senior Beijing official on Friday.

Beijing municipal deputy mayor Li Shixiang, also a deputy to the nation's top legislature, revealed the figure during a group discussion at the ongoing "two sessions". It is the first time that the Chinese capital put forward a new target after its population grew much faster than expected.

In 2005, the State Council, or China's cabinet, set the goal of having a total of 18 million people for Beijing in 2020.

Currently, the city's population has surged to 21.54 million and the city will allow a small rise to no more than 21.8 million by the end of the year.

The targeted population of 23 million was calculated based on the capability of the city's water resources to support its residents, according to the deputy mayor, as the South-to-North Water Diversion project has not brought a fundamental change to improve the water shortage situation.

Overcrowding has exacerbated the city's traffic and environmental problems.

Premier Li Keqiang said in his report on the work of the government that the fight against "urban diseases", such as air pollution and traffic congestion, must be stepped up to improve people's living standards.

Fighting pollution continues to be a priority as the government pledged to cut energy intensity by 3.1 percent and reduce emission of major pollutants, said Li.

From 2014, the city began to relocate some of the businessmen in the wholesale markets near Dahongmen and Beijing Zoo to nearby cities in its neighboring Hebei province.

A clothing market in Langfang, Hebei province, which opened at the beginning of this year, boasts 150,000 square meters in construction area and nearly 4,000 booths. More than 80 percent of its salesmen are from the two wholesale markets in Beijing.

In the future, Beijing will continue to relocate industries viewed as unhealthy to its development and focus on its role as the country's capital, the vice-mayor said.

The city also plans to control its average level of PM2.5 at 60 micrograms in one cubic meter of air.

Li said further efforts are needed to advance the coordinated development of the Beijing-Tianjin-Hebei area.