A Japanese court has ruled that Okinawa Gov. Takeshi Onaga's revocation of a reclamation permit for a U.S. military base on the southern island was illegal, supporting the central government plan to go ahead with the reclamation despite protests by local residents.

Friday's decision is the latest development in a legal battle between Okinawa and Tokyo over the relocation plan that has stalled for 20 years. Okinawa said it will appeal the Fukuoka High Court ruling to the Supreme Court.

Onaga revoked approval for the permit last October. The reclamation is needed so the U.S. can relocate Marine Corps Air Station Futenma to a less populated area on the island.

Many residents complain about the large American troop presence on Okinawa and want the Futenma base closed instead of moved.