BEIJING, July 10 (Reuters) - China may encourage more of its 1.3 billion people to work overseas as a way of easing population pressure, a senior official said on Tuesday, adding it would not significantly alter strict family planning rules.

Yu Xuejun, spokesman for the National Population and Family Planning Commission, told a Web cast on the central government's Web site (www.gov.cn) that its job was as much about tackling these pressures as preventing new births.

"Family planning is of course not the only way to cut the population, it can only be one way," he said. "We have many means for places with a lot of people or with great population pressures, like immigration or exporting labour.

"For example, there are more than 800,000 people from Sichuan who leave every year to work outside the province. Is this not a way of cutting population pressure there?" he said of the populous, landlocked southwestern province.

The country had 20 percent of the global population but accounted for only less than 1 percent of expatriate labourers, Yu said, adding Philippine workers were now even beginning to show up in China. "About a tenth of the population of the Philippines and Mexico work abroad any one year, which is a big inspiration for us," he said.

For more than 25 years, China has limited most couples to one, or in some cases two children, as it sought to control its ballooning population.

Yu said while the situation was generally stable, poor enforcement or miscounting in some areas had meant population growth was rebounding in some areas.

"Some regions and government officials do not know enough about the long-term and complicated nature of family planning, are too optimistic in estimating low birth rates and so pay less attention to their work," he said.

"And some places only report the good news, and not the bad."

Some of the estimated 200 million migrant workers returning to their villages with children they had in the cities in tow also skewed the statistics, as their children's births had previously not been recorded, Yu added.