Japan's mediation committee has rejected the Okinawa government's request for adjudication in a dispute with the central government over a landfill project to relocate a US military base within the prefecture.
The southwestern prefecture filed the request last November with the committee, which handles disputes between the central and local governments.
Okinawa insisted that the land minister's decision in October to temporarily suspend the prefecture's retraction of its permission to conduct landfill work was illegal. Following the decision, the Defense Ministry began the landfill work in the Henoko area of Nago City.
The committee has been studying whether the case should be subject to screening.
Committee members on Monday unanimously decided to reject Okinawa's request.
They said the minister's decision of suspension does not qualify as a dispute that requires the committee's examination because it does not constitute involvement by the central government.
In 2015, the committee made a similar decision when Okinawa sought arbitration to block landfill work.
The Defense Ministry says its policy to continue the landfill project remains unchanged.
The Okinawa prefectural government says it has begun preparations to file a lawsuit within 30 days over the land minister's decision.