The U.S. will remain the Philippines' only military ally, Foreign Affairs Secretary Teodoro Locsin said, amid an increased Chinese presence near a disputed island in the South China Sea.

The U.S. is "the only world power that is a bastion of democracy and human rights, is and will remain our only military ally. We don't need any other," he tweeted Sunday.

Relations are improving between the U.S. and the Philippines, which shifted toward China after President Rodrigo Duterte took power in 2016. More than 7,000 soldiers from the Philippines and the U.S. are participating in this year's annual joint military drills, which are taking place despite Duterte's 2016 call for a split with Washington.

The Philippine leader has questioned whether the U.S. would defend his country if China seizes disputed reefs and shoals in the sea. U.S. Secretary of State Mike Pompeo assured in March that a defense treaty would apply if Philippine vessels or planes are attacked in the waters.

Locsin's comments were made in response to a Twitter user's suggestion the Philippines ignore the International Criminal Court after the U.S. moved to revoke the travel visa of prosecutor Fatou Bensouda. They came days after Duterte — in a rare rebuke to China — warned that if it did not "lay off" the Philippine-occupied Thitu Island, where more than 200 Chinese ships have been spotted in recent months, we would order his soldiers to defend it with "suicide missions."

Locsin also tweeted that he "would not regret" climate change and rising sea levels if it covered the waters' disputed reefs and "exposes the foolishness of taking and weaponizing them."