Beijing saw the highest annual growth in its population in seven years in 2007, when the population increased by 520,000, equivalent to a middle-sized city, said a spokeswoman for the municipal statistics bureau on Monday.

Yu Xiuqin, deputy director and the spokeswoman of the bureau said at a news briefing that the total population in the national capital reached 16.33 million in 2007 with 12.13 million permanent, registered residents and 4.19 million transients, who remained in the city for part of 2007.

The increase in permanent, registered residents and transients was 157,000 and 363,000, respectively, on the figures of 2006, said Yu.

She said that the city's population is approaching the 18 million capacity limit, bringing huge pressures on environmental protection, traffic and water resources.

"The swelling population has become the root to all problems that have affected the city's economic development," said Yu.

She said that the city's population density was 995 people per square km in 2007, which was 32 people more than that in 2006. The population is clustered in the city proper, where the density was 22,394 people per square kilometer.

(Xinhua News Agency January 22, 2008)