Japan Surplus With U.S. Up 51% in May : Trade: The increase is the biggest in more than six years and is expected to fuel tensions between the two countries.

TOKYO — Japan’s trade surplus with the United States soared 51% last month, the biggest increase in more than six years, the government said Thursday, news that is likely to worsen the trade tensions between the two countries.

Japan’s overall surplus rose to an unadjusted $7.87 billion from $4.16 billion in May, 1991, the Finance Ministry said. It was the 17th straight month of increases.

Customs-cleared exports rose 4.1% to $25.46 billion, while imports plummeted 13.3% to $17.6 billion, the ministry said.

Economists said the unbroken string of surpluses will add to Tokyo’s burden at next month’s Munich summit of the G-7 industrialized countries.

“I am sure stimulation of Japanese domestic demand will be the top item on the agenda of the G-7 summit in July,” said Nobuyuki Saji, economist at Nikko Research Center.

Leaders from the G-7 nations--the United States, Japan, Germany, France, Britain, Italy and Canada--will meet July 6-8 in Munich.

Japan’s purchases of foreign fuel, machinery, chemicals and food all declined by between 6% and 15%.

The gap in two-way trade with the United States--Japan’s most vocal trade critic--widened to a $2.92-billion surplus in May from $1.93 billion a year earlier.

The 51% increase was the biggest since March, 1986, when the surplus shot up 61.7%.

While Japanese exports to the United States rose 3.3% to $7 billion, imports of American goods plunged 15.9% to $4.1 billion, the ministry said.

Japan, long the target of U.S. criticism for alleged unfair trading practices, hit back this week with a report accusing the United States of flouting international trade rules.

Washington retorted that Japan had nothing to say in this debate. “People who live in glass houses should be careful about their stones,” White House spokesman Marlin Fitzwater said.