The realignment makes final a February deal that separated a 2006 accord to move the troops and relocate the Marine Corps Air Station Futenma on Okinawa to another part of the island. Local residents and politicians have called for the base to be moved elsewhere, citing pollution and crime and the issue led to Japanese Prime Minister Yukio Hatoyama's resignation in 2010.
Under the original deal, 8,600 Marines and 9,000 dependents were to be transferred by 2014 to Guam, a U.S. territory in the Pacific almost 1,500 miles (2,414 kilometers) south of Okinawa. Now, the Obama administration is seeking a less costly plan in a time of defense spending cutbacks even as it places added emphasis on projecting force in the Asia-Pacific region.
Japan currently pays about 188 billion yen ($2.3 billion) a year to host 38,000 American military personnel and 43,000 dependents as part of a 52-year security treaty. More than 75 percent of the bases are on Okinawa, about 950 miles south of Tokyo.
About 4,700 of the 9,000 personnel leaving Japan will be relocated to Guam, according to a Defense Department official who briefed reporters on condition of anonymity ahead of the announcement. About 10,000 U.S. Marines will remain on Okinawa, the official said.
The Obama administration's plans to move Marine Corps expeditionary forces out of Japan are no longer contingent on progress in building a new site at Camp Schwab, near the Okinawan town of Henoko. The U.S. and Japan reaffirmed in the accord the commitment to building a replacement site at Camp Schwab.
Japan's bill for the relocation of the U.S. Marines to Guam will be $3.1 billion in 2012 dollars, the defense official said. The U.S. is projecting the total cost of the military buildup in Guam at about $8.6 billion, including the portion paid by the Japanese government. The U.S. defense official said the amount is a preliminary estimate.
The U.S. and Japan are also discussing possible joint military training on ranges in Guam and the Northern Mariana Islands, a move envisioned to boost the relationship between the U.S. forces and the Japan's Self-Defense Forces, according to the Defense Department official.
The U.S. Congress may reject any plan to move Marines from Japan until the Defense Department submits an independent assessment of its strategic posture in the Asia-Pacific region, Senators Carl Levin, John McCain and Jim Webb said in an April 24 letter to Panetta. Levin, a Democrat from Michigan, is chairman of the Senate Armed Services committee; McCain of Arizona is the top Republican on the panel; and Webb, a Virginia Democrat, heads a subcommittee.
The three senators said in a statement that "we still have many questions about the specific details" of today's agreement, and "will also continue to await the findings and recommendations of the independent assessment."
The independent study is due to be completed in late June, according to the Defense Department official.