Japan's trade surplus with the United States widened 38.8 percent in October from a year earlier to 577.2 billion yen ($5.77 billion) as exports surged at a much faster pace than imports, according to preliminary figures released by the Finance Ministry this week.

It was the 10th straight monthly expansion on a year-on-year basis.

Japan's exports to the U.S. rose for the 10th successive month in October on a year-on-year basis, soaring 26.4 percent to ¥1.164 trillion ($11.64 billion), while its imports from the U.S. increased for the seventh consecutive month in October, jumping 16.2 percent year-on-year to ¥586.9 billion ($5.87 billion).

The sharp rise in U.S.-bound shipments was led by autos, auto parts and motors, which swelled 39.0 percent, 16.4 percent and 19.8 percent, respectively, in terms of value.

The robust growth in imports from the U.S. was led by liquefied petroleum gas, scientific and optical equipment and motors, which ballooned 301.5 percent, 29.6 percent and 31.0 percent, respectively, in terms of value.

The U.S. is Japan's second-largest trading partner after China. Japan is now the world's third-largest economy after the U.S. and China and is heavily dependent on exports for growth.

Japan posted a trade deficit of ¥1.090 trillion with the rest of the world in October, up 96.1 percent from a year earlier and the biggest amount on record for the month. It was the 16th straight monthly trade deficit, the longest streak of deficits on record.

Japan's overall exports rose for the eighth month in a row in October on a year-on-year basis, expanding 18.6 percent to ¥6.105 trillion, while its overall imports climbed for the 12th month in succession, surging 26.1 percent to ¥7.195 trillion.

The jump in Japan's overall exports was led by autos, mineral fuels and organic compounds, which soared 31.3 percent, 80.8 percent and 38.3 percent, respectively, in terms of value.

The steep growth in Japan's overall imports was led by crude oil, liquefied natural gas and electronic parts, including semiconductors, which spiked 67.8 percent, 39.4 percent and 50.8 percent, respectively, in terms of value. A weaker yen also pushed up the value of Japan's overall imports.