The U.S. trade deficit narrowed in September as exports increased, suggesting the economy expanded more than previously believed in the third quarter.

The seasonally adjusted monthly trade gap fell to $41.55 billion, the smallest deficit since December 2010, the Commerce Department said on Thursday. Analysts were expecting the trade gap would widen to $45.0 billion.

The reading suggests exports did more to boost economic growth in the third quarter than previously believed. Gross domestic product expanded 2.0 percent in the period, according to initial estimates.

U.S. exports rose 3.1 percent in September, the biggest increase in more than a year despite a debt crisis in Europe that has weighed on the global economy.

Exports to the European Union were flat compared to the prior month, although the figures were not adjusted for seasonal swings. Unadjusted exports to major trade partners Canada and Mexico fell in the same period.

U.S. imports rose 1.5 percent in September when seasonally adjusted.

The trade deficit with China expanded in September to $29.1 billion from $28.7 billion a month earlier. The government does not seasonally adjust that reading.

(Reuters)