Deputy Prime Minister Taro Aso has said that Japan would consider a Chinese invasion of Taiwan as a threat to national security, and that Japan would help the U.S. in defending the self-ruled island.
"If a major incident happened (over Taiwan), it's safe to say it would be related to a situation threatening the survival (of Japan)," Aso said during a speech in Tokyo. "If that is the case, Japan and the U.S. must defend Taiwan together."
With his remarks, Aso became the highest-ranking government official to outline a specific scenario in which Japan's Self-Defense Forces would be deployed to assist in the defense of another country or region.
Although Japan's war-renouncing Constitution restricts the use of its SDF, security laws enacted in 2015 allow for its deployment outside the country, including assisting an ally or friendly nation in the event of an attack that threatens the nation's security, a concept known as collective self-defense.
Aso, who is also finance minister and a member of the country's National Security Council, is known for being outspoken, and it is unknown how much weight his statements held.
Asked about Japan's position on the cross-strait issue during a news conference Tuesday, Aso said that any conflict over Taiwan should be settled through discussion, and that Japan was closely following the situation.
Meanwhile, Orient Shield, the largest annual US-Japan military exercise, began June 24. According to the Orient Shield Facebook page, this year's training session, which concludes July 11, is the 36th iteration of an exercise that aims to "enhance interoperability and test and refine multidomain and cross-domain operations."
In April, the U.S. and Japan issued a joint statement emphasizing peace and stability in the Taiwan Strait and encouraging peaceful resolution of cross-strait disputes.
China's increasingly aggressive behavior in the Taiwan Strait has become a major area of concern for Japan.