NARITA, Chiba Pref. — New U.S. Ambassador to Japan John Roos arrived in Tokyo Wednesday pledging to further strengthen bilateral ties and solidify the bond he called the cornerstone of Washington's Asia-Pacific policies.

Roos, sworn in as ambassador Sunday, will fill the spot left open since the January departure Thomas Schieffer.

"I am deeply honored to be the U.S. ambassador to this great nation of Japan," Roos told reporters at Narita airport. "Ties between our two countries are unique," he added, expressing hope that Tokyo and Washington continue to play further roles together in promoting security, stability and democratic values in the world.