As protesters and police continue to clash over the restarting of construction work on helipads in Okinawa Prefecture earlier this month, the U.S. military reiterated Friday that it plans to return some 4,000 hectares (9,900 acres) of land in the prefecture to Japan in an apparent attempt to ease local anger.

The return of part of the Northern Training Area — which would be the United State's largest handover since the island's reversion to Japanese control in 1972 — was agreed upon between Tokyo and Washington in 1996.

But since Japan has failed to uphold its part of the deal to build replacement helipads — a precondition for the return — the return has languished for two decades.