WASHINGTON (Yonhap News) ― As it broadens its alliance with Japan, the United States should nonetheless consider the growing anxiety among neighboring nations over Tokyo’s apparent flexing of its military muscles, officials here said Thursday.

Washington’s push for strengthening bilateral and trilateral alliances with Seoul and Tokyo is no news. But unnerving South Korea and China is the conservative Japanese administration’s stated goal of expanding the role of its self-defense forces.

At a rare gathering of the foreign and defense ministers of the two sides in Tokyo this week, the U.S. formally welcomed Japan’s efforts to play a bigger role in regional security and stability, including a controversial pursuit of exercising the right to “collective self-defense.”

It would allow Japan to launch a counterattack if an ally is attacked by a foreign nation.

Asked to specify its position on the matter, the U.S. State Department emphasized the importance of the alliance with Japan, “which forms the cornerstone of our engagement in the Asia-Pacific, and to a secure and stable region.”

“It is up to the Japanese people and government to determine Japan’s capabilities,” a department official told Yonhap News Agency, saying it’s Washington’s formal position on the matter.

South Korean officials are apparently reluctant to speak in public about Washington’s approach toward Tokyo’s move to expand its military role.