Japan and the U.S. will finalize the details of the relocation of the Futenma air base in Okinawa by early September, Chief Cabinet Secretary Hirofumi Hirano said Wednesday, leaving the most contentious elements unresolved until after the July Upper House election.

The delay in announcing the details, including where and how the base's operations will be moved, is apparently due to the continued opposition to the relocation by the Social Democratic Party.

The Democratic Party of Japan needs the SDP's cooperation in the Upper House poll.