Japan's current account surplus narrowed by a record amount in June as exports fell and higher oil prices pushed up the import bill.

The surplus shrank 67.4 percent to ¥493.9 billion from ¥1.52 trillion a year earlier, the Finance Ministry said Wednesday. The median estimate of 29 economists surveyed by Bloomberg News was for the gap to decrease to ¥494.7 billion.

Rising energy and raw materials costs are taking a toll on sales abroad as well as spending by companies and consumers at home, threatening the nation's longest postwar expansion. The economy shrank last quarter, bringing the country to the brink of its first recession in six years.

"Japan has been in an economic downturn since the end of last year and the downturn may last 12 to 18 months," said Susumu Kato, chief economist at Calyon Securities in Tokyo. "Both domestic and external demand may remain weak."

Exports fell 1.5 percent in June from a year earlier, the first fall since November 2003, Wednesday's report showed. Imports climbed 17.8 percent to a record ¥6.59 trillion. Japan imports virtually all of its oil. Crude oil surged to a record $147.27 a barrel on July 11.

Higher import costs are being reflected in wholesale prices, which rose 7.1 percent to a 27-year high in July from a year earlier.

The narrowing of the surplus was limited by returns on investments made overseas.