BEIJING, March 1 (AFP) - China will press ahead with its controversial family planning system to keep its population under 1.3 billion by the turn of the century, Premier Li Peng said Saturday.

"We shall not slacken our efforts in family planning and we will improve the system whereby governments at all levels are responsible for attaining their quotas on birth control," Li said.

He said special attention would be directed at rural areas and the migrant population, where many couples have managed to evade the long hand of officialdom, either through bribery or by moving.

Under the restrictions, urban dwellers can only have one child per couple.

In rural areas, two children are generally allowed, while ethnic groups such as the Mongols, Tibetans and Uighurs are permitted two and sometimes three children.

China introduced its strict family planning system in the early eighties after witnessing exponential population growth which threatened food and water supplies.

China's population officially reached 1.2 billion in February 1995, although researchers fear that large numbers of unreported births could push that figure higher.