HONG KONG  As most countries agonize over how to keep their barely reviving economies growing, China is already looking to slam on the brakes.

China’s central bank moved late Friday to reduce lending to companies and individuals by requiring large commercial banks to increase the amount of cash they park with the central bank. The move, which came earlier than most economists had expected, was meant to slow China’s breakneck economy and inflation.

It was the second time in a month that the central bank had directed the country’s banks to increase reserves. In spite of the earlier edict, which took effect on Jan. 18, banks actually lent more money in January than in the previous three months combined, illustrating just how hard it is for Beijing to modulate its rapidly expanding economy.

Chinese economists now predict the economy will grow about 10 percent this year, while Western economists put the figure closer to 12 percent. The growth reflects a revival of exports, strong consumer spending and heavy government investment in infrastructure projects like high-speed rail lines.