It is the latest move by the allies, which have repeatedly expressed alarm over China’s growing assertiveness in Asia.

Japanese Defense Minister Shinjiro Koizumi made the announcement in a news conference Wednesday night in the central Philippine province of Cebu, where he met U.S. Defense Secretary Pete Hegseth on the sidelines of an annual meeting of Southeast Asian defense chiefs and their major Asian and Western counterparts.

Koizumi renews concern over China’s naval activity

Koizumi raised concern Thursday about China’s increasing naval activity in southwestern Japan. He said that three Chinese destroyers and a coast guard ship together crossed the Osumi Strait south of the southern main island of Kyushu and headed east to the Pacific Ocean this week. It was the first such fleet configuration his ministry has spotted, he said.

Koizumi said he cited the incident as “an example illustrating the challenging security environment in the region” in his remark at a session Thursday. His ministry will keep watching the Chinese activity with high level of interest, he said. Japan has been accelerating military buildup in southwestern Japan to deter China.

The annual meetings aim to avert a major regional conflict and strengthen defense cooperation. On the sidelines of the meetings, however, the U.S. and China and their allies have often traded criticisms.

Japan, US to bolster joint missile production capacity

The missiles that will be produced as part of a joint effort called “Operation Supercharge” are essential for the F-35 fighter jets, Koizumi said. The two sides agreed to build a final assembly and inspection plant for the Advanced Medium-Range Air-to-Air Missile, or AMRAAM, in Japan, he said. The U.S.-made F-35s are one of the world’s most advanced aircraft and are also used by the Japanese military.

During his brief meeting with Hegseth in Cebu, Koizumi said he “shared a sense of crisis … regarding the increasingly severe regional situation and we agreed to strengthen the deterrence and response capabilities of the Japan-U.S. alliance with greater speed and intensity than ever before.”

“We reaffirmed the importance of a free and open international order based on the rule of law, which rejects any attempts to unilaterally alter the status quo through the use of force, coercion or other means,” Koizumi said.

Hegseth reassures US engagement in the region

Hegseth renewed the Trump administration’s repeated assurances of commitment to help deter aggression in the region in a separate meeting on Wednesday with ASEAN defense ministers, who were led by the host, Philippine Defense Secretary Gilberto Teodoro Jr. Like Koizumi, Hegseth did not mention China by name in expressing his security concerns in the region.

“The approach we’re taking, we describe as strong, quiet and clear,” Hegseth told the ASEAN defense chiefs. “Strong enough to deter coercion and aggression, quiet enough to avoid needless escalation or public theatrics to let our actions speak for themselves.”

His message is “clear enough that our friends, our partners and potential adversaries understand precisely where the United States stands and that we will defend our interests and the interests of our allies and partners,” Hegseth said.

Hegseth has assured the Philippines, the oldest treaty ally of Washington in Asia, that the Trump administration will build a robust deterrence against China’s increasingly aggressive actions in the disputed South China Sea. Beijing claims the busy waterway, a key global trade route, virtually in its entirety.

Australia shows commitment to defend the rule of law in the Pacific

Australian Defense Minister Richard Marles said his country’s forces, along with allies like the U.S., will press on with efforts to defend the rule of law despite China’s increasing assertiveness, including in the South China Sea. Australia protested last year after a Chinese J-16 fighter aircraft released flares and passed within 30 meters (100 feet) of an Australian P-8 Poseidon surveillance jet over the disputed waters.

“That doesn’t deter us from doing what we need to do and that’s essentially asserting the rules-based order here in the end of the Pacific,” Marles told The Associated Press in Cebu on Wednesday. “Freedom of navigation on the high seas is profoundly important for Australia.”

The Philippines, Vietnam, Malaysia and Brunei, all ASEAN member states, along with Taiwan, also have overlapping claims in the South China Sea. Confrontations have particularly escalated between Chinese and Philippine coast guard and navy vessels in disputed shoals and outlying waters.

Washington has warned that it’s obligated to defend the Philippines if Filipino forces, ships and aircraft come under an armed attack, including in the South China Sea.

Beijing and Tokyo have a separate dispute over tiny Japanese-controlled islands in the East China Sea, with both sides often accusing the other of infringing on their maritime territory.

___

Associated Press journalists Aaron Favila in Cebu, Philippines, and Haruka Nuga in Bangkok and Mari Yamaguchi in Tokyo contributed to this report.