The Japanese government is set to approve, in place of the prefectural government, ground improvement work as part of a project to relocate a US Marine base in Okinawa Prefecture.

The central government plans to relocate the US Marine Corps Futenma Air Station from densely populated Ginowan City to a site at Henoko, Nago City, despite the opposition of the Okinawa government.

Okinawa officials have defied a high court ruling ordering the prefecture to approve related ground improvement work at the offshore site by Monday.

Land Minister Saito Tetsuo is expected to give the green light to the work on Thursday morning. It is the first time for the central government to override a decision by local authorities based on the local autonomy law.

Following the approval, the Defense Ministry plans to start ground improvement work at the relocation site in mid-January.

Okinawa Prefectural Governor Tamaki Denny on Wednesday appealed the high court ruling to the Supreme Court. He said the decision does not give consideration to the will of many Okinawa residents and the true public interest.