Soviet citizens are increasingly fleeing the farms for a better life in the already strapped cities, a troublesome trend that threatens to worsen the country's economic problems, officials said Saturday.

The Soviet population climbed 9.3 percent during the past decade and now stands at 286.7 million, with the largest increases in the central Asian regions, according to census figures published Saturday.A top Soviet statistician expressed concern the population had not increased faster - which he said was necessary to ensure greater economic development - and that growth rates were low in European regions.

Pravda, the Communist Party daily, devoted an entire page to preliminary results of the nationwide census conducted in January, the country's first since 1979.

The demographic center of the Soviet Union is gradually shifting from the European Slavic heartland - the Russian federation, the Ukraine and Byelorussia - to Central Asia, according to data from the State Committee on Statistics.

Those numbers represent troublesome trends for the Soviet leadership, which has been trying to keep the country's peasantry on the farm and has acknowledged it cannot create jobs fast enough in Central Asia to keep pace with population growth.

The total number of Soviets grew by 24.3 million in the past 10 years and stood at 286.7 million Jan. 12. That represents a growth of 9.3 percent since 1979.

Four traditionally Moslem republics in Soviet Central Asia registered the greatest population increases: a 34 percent rise in Tadzhikistan, 29 percent in Uzbekistan, 28 percent in Turkmenia and 22 percent in Kirghizia.

Azerbaijan, the only predominantly Moslem republic in the Soviet Caucasus, had a 17 percent increase in population, and in the fifth Central Asian republic, Kazakhstan, the number of people rose 13 percent.

Population growth in the rest of the country did not exceed 10 percent.