The U.S. trade deficit rose to 40.6 billion dollars in December, an increase of about 6 percent from the previous month, as the value of imports grew faster than exports, the U.S. Commerce Department said on Friday.

The Commerce Department said that total December exports of 163. 0 billion dollars and imports of 203.5 billion resulted in a goods and services deficit of 40.6 billion, up from a revised 38.3 billion dollars in November.

The rising exports in December, the best reading since July 2008, were led by sales of industrial machinery, civilian aircraft and autos and auto parts.

However, imports rose even faster. A 2.6-percent gain pushed total U.S. imports to 203.5 billion dollars, the highest level since October 2008, led by a 16.8-percent rise in imported oil. The average price for a barrel of imported crude oil climbed to 79.78 dollars in December.

For all of 2010, the U.S. exports of 1,831.8 billion dollars and imports of 2,329.7 billion resulted in a trade deficit of 497.8 billion, a 32.8-percent surge from 2009.

In 2009, affected by the great financial crisis, the U.S. trade deficit dropped to the lowest point in eight years.

Economists believe that the U.S. trade deficit is going to continue widening in 2011. However, a weaker dollar will benefit U. S. exports.