Exercises begin three days after William Lai Ching-te took his oath as president of the island China claims as its own.
Together with neighbouring Indonesia and Australia, the region is home to some of the oldest evidence of human life.
Lam’s appointment comes after a major anticorruption drive that analysts say he has weaponised for his benefit.
Countries must protect oceans by reducing fossil fuel emissions, world court rules as island states fight for survival.