The government on Monday left unchanged its assessment of the economy for April, but it expressed caution amid concerns over the U.S.-led war in Iraq, the future of the U.S. economy and the spread of severe acute respiratory syndrome across Asia.

"While the economy has become roughly flat, uncertainty still remains," the Cabinet Office said in the monthly economic report for April, using roughly the same wording as a month earlier.

The March report said, "While the economy has become roughly flat, uncertainty is increasing due to the situation surrounding Iraq."