Beijing's population is approaching the saturation point, Wei Chenlin, director of the municipal bureau of land and resources, said on Tuesday.

The population upper limit for the city, according to the bureau of land and resources, is 18 million. Currently the population has surpassed 16.3 million.

It is estimated that by 2020 the population will be 21 million.

Wei said the present population is already putting great stress on land use.

"It is of great urgency we improve the efficient use of land and resources," he said.

Beijing covers an area of 16,400 sq km, but only 6,000 sq km is exploitable, and it is not being put to good use, Wei said.

"In the first six months of this year, about 5.05 sq km of the 8.8 sq km of newly acquired land was illegally developed in 14 districts and counties of Beijing, taking up 57 percent of the newly acquired land area," Wei said.

The major reason for this was illegal occupation of land by county governments and property developers.

However, Zhang Yi, an expert from the Institute of Population and Labor Economics, said it was difficult to set an "upper limit" for Beijing's population.

"The population bearing capacity of a city is not determined only by its land resources, but also by its social structure and economic development," he said.

"Beijing still has room for exploitation. If it had more multi-centers in the city, population distribution would be more even and more people could be accommodated," he said.

Zhang, who believes Beijing has the potential to accommodate more people said: "The government should pay more attention to the efficient, scientific use of land to improve the city's population bearing capacity. Disordered development will harm it."

The municipal bureau has vowed to crack down on illegally occupied arable land.

Questions:

1. What is the current size of Beijing’s population?

2. By 2020 the population is estimated to be how large?

Answers:

1. Approximately 16.3 million.

2. 21 million.