Visiting top U.S. military officer Martin Dempsey met here Friday with Japanese military chiefs and vowed to cooperate closely with Japan on defense to cope with regional threats.

Dempsey, chairman of the U.S. Joint Chiefs of Staff, held talks with Japanese Defense Minister Itsunori Onodera and Chairman of the Self-Defense Forces'Joint Staff Shigeru Iwasaki and reaffirmed U.S. commitment to defend Japan under their bilateral alliance.

"Tensions are high in the region," said Dempsey. "We are working closely...there are also opportunities that come of that for greater cooperation, greater integration and interoperability and we are eager to take advantage of those opportunities," the U. S. top officer told reporters after the meetings.

Dempsey also addressed Japan's National Defense Institute for Defense Studies Friday afternoon and said the United States remains a reliable partner for its allies in the Asia-Pacific region, and U.S. presence has been there for over 200 years and never left.

He said his country's Asia-Pacific strategy is based on its alliances with regional countries and the alliances are "strong and getting stronger."

Dempsey said the United States will also further involve in regional affairs and "pay more attention and to engage more often in the region, not just Northeast Asia, but in Southeast Asia and across the region."

The U.S. top uniformed officer, who arrived at Japan on Thursday, is on an Asia-trip that already took him to South Korea and China.