Aging population poses a huge challenge to China's pension system, minister of human resources and social security Yin Weimin said Tuesday.

The country's population is rapidly aging, and there are 170 million people over the age of 60, who account for 12.8 percent of the total population, Yin said.

"How to increase pension has become a problem to deal with the aging population," the minister said at a press conference on the sidelines of the ongoing parliamentary session.

Last year, a total of 1.3 trillion yuan (197.9 billion U.S. dollars) of pension premium was collected and about 1 trillion yuan was handed out, resulting in a balance of 300 billion yuan, he said.

That added up to a combined pension balance of 1.5 trillion yuan by 2010, he said, adding the country has no difficulty in paying pension.

Yin added that by the end of last year, China's national social security funds exceeded 700 billion yuan.

The government would improve measures on investment of the national social security funds to maintain and expand its total value along with the country's economic growth, he said.