US “freedom of navigation” operations in the South China Sea declined last year, as it relied more on the Philippines and uncrewed drones for reconnaissance flights over the contested waters, a Beijing-based think tank found.

The think tank said that as large American vessels such as aircraft carriers and amphibious groups faced growing maintenance and deployment constraints such as the Middle East conflict, Washington had changed the nature of its presence in the Asia-Pacific region.

Yet, the region remained a priority, the Beijing-based South China Sea Strategic Situation Probing Initiative said in a report released on Thursday.

“Regardless of strategic adjustments by the second [Donald] Trump administration or the evolution of other global hotspots like the Middle East, the broader Asia-Pacific region, particularly the South China Sea, will remain the US military’s most critical strategic theatre,” it said.

The report added: “The frontline US military operations may become increasingly aggressive and provocative.”

Last year, America conducted just two public freedom-of-navigation operations in the disputed waters, the same as in 2024, but fewer than the six times it carried out in 2023 and the four in 2022, according to the report.