The U.S. trade deficit widened slightly in May, reflecting declines in sales of American-made aircraft and machinery as exports continued to suffer from a strong dollar.

The deficit grew by 2.9 percent to $41.9 billion, up from an April figure of $40.7 billion, according to the U.S. Department of Commerce.

Overseas sales of U.S.-made goods declined by 0.8 percent to $188.6 billion as American exporters have been hurt this year by a rising value of the dollar, which makes their products less competitive in international markets.

At the same time, the agency said, imports in May fell 0.1 percent to $230.5 billion.

Even with the slight rise during the month, the deficit over the past two months is averaging less than in the first quarter, a development that, analysts say, should help boost growth in the second quarter and play a major role in jump-starting a sluggish economy over the long term.

They forecast a rebound to an annual growth rate of around 2.5 percent, as measured by the gross domestic product, in the second quarter with export volume boosted by the recent extension of presidential Trade Promotion Authority and the prospect of far-reaching transpacific and transatlantic free trade agreements.

On a country basis, the U.S. ran a rare trade surplus with its biggest trading partner, Canada. The $644 million surplus was the first monthly surplus with Canada going back to 1990.

However, the U.S. trade deficit with China – the largest with any country – jumped 15 percent to $30.5 billion in May. So far this year, the gap is running 11.1 percent higher than the same period a year ago.