TOKYO >> U.S. Sen. Daniel Inouye said Tuesday he expects the fate of a contentious American Marine base in southern Japan will be decided next month.

U.S. and Japanese foreign and defense ministers are to meet in late June to decide what to do with the Marine Corps Air Station Futenma, which is supposed to be moved to a less populated part of Okinawa under a 2006 agreement. Local residents, however, say it should be moved off the island.

Inouye, who is chairman of the Senate Appropriations Committee, downplayed a letter written by three colleagues earlier this month that called for a reevaluation.

Senators John McCain, Carl Levin and Jim Webb said the Defense Department should rethink its overall plan to restructure American forces in East Asia, calling it “unrealistic, unworkable, and unaffordable.”

The senators said the agreement, aimed at decreasing America’s military footprint in Japan, imposes an enormous financial burden on Tokyo as it recovers from a major earthquake. They offered alternatives they said would save billions of dollars but still keep U.S. military forces in the region.

Inouye said the letter expressed concern about Japan’s ability to “bear their load” amid the disaster.

“We have been assured by the Japanese government that yes they can,” Inouye told reporters in Tokyo. “I think both governments agree that American presence is necessary and desired.”

He said U.S. forces are critical for balancing a rising China, which is bolstering its military might. If Americans left, Japan would have to increase its military strength, he said.

“One can be assured that if this ever happens, nations in the neighborhood will do the same,” he said. “And if there’s an arms race in this area, you can almost conclude, because history has given us this lesson many times over, there will be bloodshed.”

Okinawans have long complained about pollution, noise, crime and other problems associated with U.S. military bases on the island, which hosts more than half the 47,000 U.S. troops in Japan. The previous prime minister, Yukio Hatoyama, was forced to resign last year after promising and failing to get the Marine base off the island altogether.

Under the 2006 agreement, the Futenma base, located in a heavily populated southern part of Okinawa, would be closed and its air operations relocated to Camp Schwab in the north, where a new airfield would be built. Some 8,000 Marines would also be shifted to the U.S. territory of Guam by 2014. Japan would foot much of the multibillion-dollar relocation bill.

Inouye said the plan emerged from “much deliberation and concern.” He said he’s hopeful the ministers can resolve the outstanding issues at the upcoming meeting.

Inouye, 86, is the longest-serving member of the Senate. Born in Hawaii, he is a second-generation Japanese-American who fought in the famed 442nd Regimental Combat Team during World War II. He has dedicated much of his political life to fostering U.S.-Japan ties.

He is visiting Japan this week to meet leaders and tour the disaster-hit northeast coast.