CAMP FOSTER, Okinawa – The Japan central government requested Okinawa’s permission Friday to build offshore U.S. military runways for the controversial relocation of the Marine Corps’ Futenma air station, according to the Kyodo news service.

The request for ocean fill permits is a crucial step in a nearly 20-year effort to close Futenma and replace it with a new air station farther north. But the plan is still strongly opposed by the prefecture’s governor and by many Okinawans, who want Marine Corps aircraft off the island.

"This is a key milestone that comes after many years of hard work between the United States and Japan,” said Pentagon Press Secretary George Little, in a statement released Friday. “It marks a significant step toward realizing the vision of the 2006 Realignment Roadmap and toward achieving a sustainable U.S. military presence with less impact on the Okinawan people.

“This effort is critical to our ongoing rebalance to the Asia-Pacific region and our ability to maintain a well-distributed and politically sustainable force throughout Asia.”

Okinawa Gov. Hirokazu Nakaima now has the option to approve or deny the project, a decision that would take up to a year, according to the Kyodo report, which quoted an unnamed official in the Okinawa government.

Nakaima repeatedly has said he cannot approve the permit request or support overhauling Camp Schwab into the island’s newest operations center for MV-22 Osprey aircraft.

The Futenma relocation has long been the linchpin in plans to reduce the military burden on Okinawa, and now is a key initiative in the shift of U.S. focus to the Pacific region.

The U.S. and Japan began the effort to reduce the number of Marines on the island and close Futenma in 1995, following the brutal gang rape of a 12-year-old Okinawan girl by two Marines and a sailor. But the effort has been fraught with delays due to uncertainty in Congress and Okinawan opposition to keeping Marine air operations on the island.

Last year, Tokyo and Washington signed a new pact that aims to relocate about 9,000 Okinawa Marines to Guam and elsewhere in the Pacific, close Futenma and replace it with a new air station elsewhere on Okinawa, and begin the return of military land to Okinawans.

An earlier 2006 agreement called for cutting the Marine Corps presence on Okinawa roughly in half by 2014, but that plan was abandoned after both countries admitted delays had made the deadline unrealistic.

tritten.travis@stripes.com

