Kurt Campbell, U.S. assistant secretary of state for East Asia and Pacific affairs, will visit Japan on Thursday for talks with top diplomatic officials, primarily on the Futenma airfield issue, sources versed in Japan-U.S. relations said.

He is expected to meet with Vice Foreign Minister Mitoji Yabunaka and possibly Foreign Minister Katsuya Okada, the sources said Tuesday.

Campbell's visit comes ahead of President Barack Obama's stay in Japan on Nov. 12 and 13, when talks between him and Prime Minister Yukio Hatoyama will likely focus on the increasingly divisive issue of where the Futenma airfield, now in Ginowan, Okinawa Prefecture, should be relocated.

The U.S. has made it clear Japan should decide before Obama's visit to stick to the existing agreement that the functions of the Futenma base will be moved to a site within Okinawa.

Hatoyama has said the administration will take its time considering the matter.