The governor of Japan's Okinawa on Wednesday rejected the central government's demand to approve its modified plan on landfill work for the relocation of a key U.S. base within the southern island prefecture.

In a letter addressed to the government, Gov. Denny Tamaki said it was "difficult to approve" the modified plan to reinforce soft ground at a designated construction site by the Wednesday deadline.

Tamaki's decision is likely to prompt Tokyo to adopt a stricter approach and move forward with a procedure that allows the land minister, rather than the governor, to approve the plan, officials said.

Okinawa Gov. Denny Tamaki speaks to the press on Sept. 27, 2023, at the prefectural government building in Naha, Okinawa Prefecture in Japan. Tamaki on the same day declined the central government's proposal aimed at obtaining the local government's approval to push ahead with landfill work for the relocation of a key U.S. base within the southern island prefecture. (Kyodo) ==Kyodo

Land minister Tetsuo Saito placed the demand as Tamaki did not respond to the Supreme Court's decision earlier this month that turned down an appeal by Okinawa, confirming Tokyo's authority to instruct the local government to approve the modified plan.

Tokyo and Okinawa have long remained at odds over relocating U.S. Marine Corps Air Station Futenma in the residential district of Ginowan to the less densely populated Henoko coastal area in Nago.

In 1996, Tokyo and Washington agreed on a relocation plan that involved returning the land occupied by the airfield. Tokyo selected Henoko as the relocation site in 1999.

Photo taken on Sept. 26, 2023 shows the Henoko coastal area in Nago, Okinawa Prefecture, under construction for the relocation of U.S. Marine Corps Air Station Futenma. (Kyodo)

But residents of Okinawa continue to strongly oppose the relocation within the prefecture, which hosts the majority of U.S. military facilities in Japan.

As next steps, the Japanese government is expected to order the Okinawa governor to accept the modified landfill plan by early October and bring the case to the Fukuoka High Court's Naha branch if Tamaki does not comply, the officials said.

If the central government wins the case and the Okinawa governor still does not approve the plan, the land minister could endorse it and initiate the landfill work, the officials said.

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