Officials from Japan and the United States involved in defense and foreign affairs began full-fledged consultations over revising bilateral guidelines on defense cooperation at working-level talks Thursday in Tokyo.

One focus of the revisions is likely to be how to beef up cooperation between the security allies in monitoring and surveillance activities as China moves to increase its maritime presence in the region.

Kurt Campbell, assistant U.S. secretary of state for East Asian and Pacific affairs, expressed hope for a greater role to be played by the Self-Defense Forces, telling reporters in Tokyo that the United States is interested in "concrete areas where the United States and Japan can work more effectively together."