MANILA, Philippines — The United States and the Philippines have wrapped up joint naval drills near the Asian nation that focused on replenishment at sea, naval warfare, and human assistance and disaster response.

The exercise took place amid ongoing tension in the South China Sea, with resupply operations stoking diplomatic spats between the Philippines and China.

Started in 2017, Sama Sama is an annual maritime training event between the Philippines and the U.S. that includes nontraditional security drills. In 2016, then-President Rodrigo Duterte scrapped military drills with the United States, including the Cooperation Afloat Readiness and Training effort and the amphibious landing exercise PHILBEX.

But President Ferdinand Marcos Jr. reimplemented joint training efforts. The Japan Self-Defense Force joined the exercise in 2019, and the Royal Australian Navy joined in 2022. The most recent iteration of Sama Sama, which began Oct. 2, also included Canada, the United Kingdom and France.

“One of the main areas we focused on is the replenishment at sea, and we saw a great capability enhancement there,” Cmdr. Jun Chen, a foreign affairs officer with the U.S. Navy’s Destroyer Squadron 7, told the press during Friday’s closing ceremony. “It opened up a lot of Philippine Navy [human assistance and disaster response] and interoperability we can do later on.”

The navies of the U.S., the Philippines, Canada, and Japan participated in shore-based and at-sea drills, while the French and Australian navies took part in subject matter exchanges and the New Zealand and Indonesian navies attended as observers.

Drills includes anti-surface, anti-submarine and electronic warfare scenarios — critical areas given the Philippines only recently acquired and equipped its guided-missile frigate BRP Antonio Luna for South China Sea operations, according to Philippine Commodore Joe Orbe, the officer in charge of Sama Sama.

“We need [to develop capabilities for] resupply at sea — transferring fuel and supplies from one ship to another,” Orbe said. “We can use these capabilities in both warfighting and humanitarian assistance.”

The exercise also saw participation by Marine Rotational Force-Southeast Asia, a U.S. Marine Corps task force dedicated to working with regional allies and partners on security initiatives.

In addition, five military ships joined: the Philippine Navy frigate BRP Antonio Luna, the U.S. Navy destroyer Dewey, the Japan Maritime Self-Defense Force destroyer JS Akebono, Royal Canadian Navy frigate HMCS Vancouver, and British Royal Navy offshore patrol vessel HMS Spey.

Other U.S. Navy assets included the dry cargo/ammunition ship USNS Wally Schirra, the replenishment vessel USNS Yukon, a P-8 Poseidon maritime surveillance aircraft, two Hawker Hunter fighters and an MH-60R Seahawk helicopter.

Regional tension

Sama Sama is particularly important in building Philippine military capacities as the country shifts from its focus on counterterrorism and counterinsurgency operations to addressing threats in the South China Sea, according to Collin Koh, a senior fellow at the Singapore-based S. Rajaratnam School of International Studies.

“The AFP [Armed Forces of the Philippines] has been basically oriented to internal security for so many decades,” Koh told Defense News. “The skills that were there were lost over the decades of internal security focus, and they are not up to scratch with modern combat. The AFP needs to gain a wide spectrum of skill sets.”

Since Marcos became president in 2022, he has taken a more aggressive stance against China in the South China Sea. Last month, during the 18th East Asia Summit in Indonesia, he urged member countries of the Association of Southeast Asian Nations to take action against China’s “dangerous use of coast guard and maritime militia vessels.”

Earlier this month, two supply boats crewed by Philippine Navy personnel and escorted by two larger Philippine Coast Guard vessels breached a Chinese Coast Guard blockade. They succeeded in delivering food, water and other supplies to Filipino marines and naval personnel stationed on a long-marooned but still actively commissioned ship, the BRP Sierra Madre, at the shallows the Second Thomas Shoal.

And this week, the Philippine military accused China of shadowing and hampering a Navy vessel on a resupply mission to Philippine-occupied Thitu Island, a feature China claims as part of its territory.

The Philippines intends to protect what it considers its archipelagic territories, including islands and features within its exclusive economic zone. It occupies these areas in what the government calls the West Philippine Sea.

The country has steadily built up its naval arsenal in recent years, acquiring frigates, fighter jets, landing dock vessels, corvettes, UAVs and missiles. An upcoming third phase in the military’s modernization program will focus on strengthening and developing assets in the South China Sea, according to Chief of Staff Romeo Brawner.

A buildup of Philippine naval capabilities is also crucial given tension over Taiwan, which China considers a rogue province and has threatened to take back by force, Koh explained. Such a conflict would likely include military activities in the greater South China Sea, he added.

China has built and militarized outposts in the sea, and it its Southern Theater Command operates in the area.

“The [Chinese People’s Liberation Army Navy’s] Southern Theater Command has two primary roles or directions: The first direction is definitely the South China Sea dispute,” Koh said. “But the second direction, or what we call the second task it’s mandated to do, is Taiwan. In the case of a Taiwan scenario ... the Southern Theater Command is supposed to secure the southern flex of the operation.”

“The AFP will be expected to do more in the West Philippine Sea in the event of Taiwan,” Koh added. “If there will be a war in Taiwan, there will be a South China Sea dimension.”

The Associated Press contributed to this report.