A blueprint for Beijing's development in the next 20 years, which caps the capital's population at 23 million and calls for more green space, has been given the seal of approval by the central leadership.

The population of Beijing will be kept to 23 million by 2020, where it will remain for the foreseeable future, according to the development plan of Beijing (2016-35) approved jointly by the Central Committee of the Communist Party of China and the State Council, China's Cabinet.

At the end of last year, the number of registered residents in Beijing was 21.73 million.

The full text of the plan has not yet been released, but a statement released on Wednesday accompanying the approval said that Beijing will be developed into the national center of politics, culture, international exchanges as well as scientific and technological innovation.

"The city planning and development of Beijing should provide services for the country's central departments, for its international cooperation and exchanges, for the development of science, technology and education, as well as for improving the living standards of people," the statement said.

The Beijing municipal government also was told to try to build the city into a world-class national capital that is both harmonious and livable.

"Public transport capacity and services should be improved in Beijing and low-carbon commuting is encouraged to relieve traffic congestion in the city," the statement said.

"Meanwhile, the environment should be improved in an all-around way through the prevention and control of air, water and soil pollution."

Feng Xiliang, director of the School of Labor and Economics at the Capital University of Economics and Business, said that the approval shows that the development plan, which sets the general direction and specific targets, has gained acknowledgment from the top leadership.

"We can see that the idea of pursuing a balanced and sustainable development runs through the whole plan," he said.

In addition, the statement also said that efforts should be made to develop a world-class city group surrounding Beijing.