The Philippines and the United States today began the largest joint military exercise ever held in the Southeast Asian nation as the two longtime allies seek to counter China’s growing influence in the region.

About 18,000 troops will take part in the exercise, which for the first time will include live fire in the South China Sea, which Beijing claims almost entirely.

One of the exercises involves the landing of military helicopters on an island in the Philippines, on the northern tip of the island of Luzon, about 300 kilometers from Taiwan.

The start of these annual high schools, which are called “Balikatan,” which means “side by side” in Filipino, comes after China’s three-day military high schools that ended yesterday, Monday. As part of these exercises, Beijing has simulated an air and sea blockade of Taiwan, which China considers a province that must be reunited with the mainland, even with the use of force.

This is the first time the annual US-Philippine High Schools are being held under the leadership of President Ferdinand Marcos Jr., who is looking to improve Manila’s relationship with Washington in the wake of their crisis under Rodrigo Duterte.

The Philippine defense and foreign ministers are scheduled to meet with their American counterparts in Washington later.

Some 12,200 US troops, 5,400 Filipinos and just over 100 Australians will attend high schools, double the number of last year. The exercises will last two weeks.

In the context of high school, the US will use, among other things, the Patriot system, which is considered one of the best air defense systems in the world.

The exercise will help improve “tactics, methods and procedures” in a wide range of military operations, said Philippine military spokesman Col. Mendel Aguilar.

In early April, the Philippines provided the US with four new military bases, including a naval base near Taiwan, angering China.

Source: APE-MPE, Reuters.