The current account surplus in May fell 8.1 percent from a year earlier, the first drop in 10 months, dragged down by slower growth of exports and a rise in the value of imports stemming from soaring crude oil prices, the Finance Ministry said Thursday.

The current account balance — the broadest gauge of trade in goods and services — came in at a surplus of ¥1.21 trillion, registering the 16th straight monthly surplus since February 2009, according to the ministry's preliminary report.

Kiichi Murashima, chief economist at Citibank Global Markets Japan Inc., said the result doesn't necessarily signal a deterioration of the economy, citing strong growth in imports as part of the reason for the narrower surplus in goods trade.

But he also warned that recent economic data indicate the recoveries in China and the United States, key export destinations, are "entering the phase of slowdown," which could affect the trade balance, while adding that Japan's economic footing is solid.

Exports climbed 33.8 percent to ¥5.03 trillion for the sixth straight month of expansion, supported by steady demand from the rest of Asia and the United States, although the pace of growth has decelerated.

Imports jumped 37.8 percent to ¥4.64 trillion, rising for the fifth consecutive month, as the value of imports expanded, reflecting a 62.6 percent year-on-year surge in crude oil prices.