Noting the “many complex factors” that would play into Beijing’s decision to attempt to unify with the self-ruled democratic island by force, including its examination of the Ukraine crisis, the commander said: “I think, to anybody that for somehow believes that we can take a breath or relax or relent on our own commitment to a ‘free and open Indo-Pacific’ … I would not support that because nature is so unpredictable.”

Taiwan and mainland China have been separately governed since they split as a result of a civil war in 1949. Beijing, which regards Taiwan as a renegade province, has since endeavoured to bring the island back into its fold.

As the Ukraine crisis has unfolded, attention has also grown on Taiwan, a potential military flashpoint that could draw the United States into conflict with China and could also pose serious security challenges to Japan, a close US ally. Taiwan is located just 170km (105 miles) away from the Japanese-controlled Senkaku Islands in the East China Sea. The islets are also claimed by China, where they are known as the Diaoyus.

As for cooperation between the United States and Japan in addressing regional security, the commander said he had “never seen greater convergence” within the alliance on realising the US strategy for the Indo-Pacific that pursues deterrence against potential aggression in the region, where China has become increasingly assertive.

He said the United States was “cultivating some options” to demonstrate US commitment to the security of South Korea in response to the North’s provocative behaviour, but did not elaborate.

Amid Pyongyang’s increased pace and scale of ballistic missile launches, the US military said in mid-March that it had conducted an exercise involving fighter jets launched from an aircraft carrier in the Yellow Sea.