Updated

TOKYO (AP) — Japanese Prime Minister Yukio Hatoyama, who will reportedly meet with U.S. Secretary of State Hillary Rodham Clinton this week, vowed Monday to do all he can to resolve an impasse over the future of a major American Marine base by the end of the month.

Hatoyama is under increasing pressure to come up with a plan to move operations off the Marine Corps Air Station Futenma on the southern island of Okinawa in keeping with a pledge he made before becoming Japan's leader last September.

He has promised to resolve the issue by the end of this month, though that goal now seems unrealistic because Okinawans oppose his suggested solutions and the United States is holding firm to an earlier agreement that Hatoyama wants to revise.

Hatoyama will meet with Clinton in Tokyo on Friday to discuss the issue, according to reports over the weekend in several Japanese newspapers. Government officials in Tokyo and Washington refused to confirm Clinton's schedule.

"I knew from the start the situation would be tough," Hatoyama told reporters Monday. "I will do all I can by the end of the month."

Okinawa hosts more than half the 47,000 U.S. troops in Japan under a security pact. To ease Okinawa's burden, Japan and the U.S. agreed in 2006 to move the sprawling Futenma air field to a less crowded part of the island, and move 8,600 Marines from Okinawa to Guam.

Hatoyama froze the 2006 deal amid local opposition and has been searching for alternatives. He has floated the idea of building a replacement airstrip on raised pilings to reduce its environmental impact on nearbly coral reefs, and of shifting training by the Marines to other areas outside of Okinawa.

Opponents on Okinawa want Futenma completely closed down and its replacement built off the island.

Last month, 90,000 Okinawans protested the base and the relocation plan — the biggest demonstration against the base ever. On Sunday, to mark the 1972 reversion of Okinawa from U.S. to Japanese administration, a human chain around Futenma drew 17,000 protesters.

Japanese and U.S. negotiators met last week in Washington to discuss the base, but the talks ended without a resolution.

About 2,000 Marines are stationed on Futenma, which is a hub of helicopter and transport plane operations.